What to do if the variator belt slips

Production of the Jatco JF011 variator began in 2005. Until 2014, it was installed on many models of different brands. And, perhaps, this is the most popular variator on our market. It is found on many Japanese cars: Nissan Qashqai, Teana and X-Trail, Mitsubishi Lancer, Galant, ASX and Outlander, Suzuki Kizashi, European: Renault Koleos, Citroen C-Crosser and Peugeot 4007 and even on American: Jeep Compass and Dodge Caliber .

The variator is compact and has fewer parts than a hydromechanical gearbox.

The variator is compact and has fewer parts than a hydromechanical gearbox.

Check algorithm when buying a car

1. Studying the service book, work orders from the service station. The service life of modern CVT gearboxes is reduced significantly if you neglect regular replacement of oil and filter elements. A suspension of wear products, washed off from the rubbing pairs by oil, is transferred to the valve body lines, where it clogs the channels and contributes to damage to the solenoids and channel walls. It is better to refuse to buy a car if the owner neglected to regularly change the oil and filters in the variator.

2. Check the oil level, smell and color.
3. Test Drive. Before purchasing, you should check the gearbox in all main operating modes.
4. Visual inspection of the transmission and variator cooling radiator. If the degree of contamination of the gearbox housing is noticeably different from other parts of the engine compartment, it is likely that the variator was recently removed for repair or replacement. Be sure to check the degree of contamination of the radiator (if one is provided for in the design), since CVTs are extremely sensitive to overheating. On many models, a clogged radiator, engine and gearbox protection when driving in traffic jams or off-road is practically synonymous with overheating.
5. Ask the owner about the vehicle's operating conditions. Many car enthusiasts kill transmissions by ignoring the rules for warming up automatic transmissions in the winter. Also, the CVT resource is reduced by careless off-road driving and towing a trailer.
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Oil condition and compliance with replacement intervals

Not all CVT transmissions are equipped with a dipstick.
On some models, you will have to contact a dealership to check the condition and level of the oil, since the hole for the dipstick is normally closed with a plug. In this case, the procedure can be neglected if the service book contains records of regular replacement, and the operation of the variator on the go does not raise any complaints. Transmission manufacturers recommend changing CVT fluid every 40 thousand km. If the vehicle is operated under difficult conditions, which include long periods of downtime in traffic jams, replacement intervals should be reduced to 30-35 thousand km. You can find a detailed discussion of checking and replacing the working fluid in the article “Correctly changing the oil in a variator.”

It is important that the process of replacing the working fluid is accompanied by resetting the aging counter. Statistics show that failure to comply with this requirement can lead to belt breakage.

Cloudy oil with a large amount of suspended friction dust indicates that it has not been changed for a long time. The smell of burning, clots of the adhesive layer are a sign of critical wear of the clutch clutch packs. Fatigue of the clutch packs will be confirmed by a failed Stall Test result.

What to look for during a test drive?

The main signs of a faulty CVT gearbox:

• jerking, jerking when accelerating;
• kicks, shocks that appear after warming up;
• shocks when changing the position of the CVT selector;
• howl, hum, coming from the transmission side when moving.

Before buying a car, the variator should be checked in the following modes: maintaining a constant speed, smooth and sharp acceleration. At the same time, on cars whose variator design requires the presence of a torque converter, it is most important to check acceleration with the accelerator pedal barely pressed.

When driving with minimal acceleration, the torque developed by the engine is only slightly greater than the rolling resistance force of the wheels and the resistance of the oncoming air flow. When checking under such conditions, the difference in the angular speed of rotation of the turbine and pump wheels is minimal (you can understand what GT slipping is if you are familiar with the design and operating principle of a torque converter-type automatic transmission).

In case of incorrect operation of the clutches or jamming of the control solenoids in the hydraulic plate, the smoothness of changing gear ratios is lost. When the difference in the angular speeds of rotation of the turbine and pump wheels is minimal, the GT does not have time to dissipate the sharp change in gear ratios. As a result, when checking before purchasing, you will more clearly feel jerks, kicks and twitches. If you noticeably increase the load (press the gas pedal harder), the GT will begin to slip more intensely and absorb defects in the operation of the clutches and valve body.

Driving sensations

If, when you press the gas pedal, the engine speed increases, but the speed remains the same or changes slightly, this is a bell about the “dying” state of the transmission. During smooth acceleration, the engine speed should remain approximately in the same position, and the speed should gradually increase. If there are sudden drops or overshoots in engine speed, then the gearbox is in trouble.

Important. When you smoothly brake to zero and selector position “D,” you will feel a slight kick. This is inevitable, because at this moment the torque converter is unlocked. The push should be small, barely perceptible.

When checking the car's variator in motion, if you feel kicks during acceleration or a strong push when the speed is reduced to zero, this is a sign of an emergency condition of the gearbox. This applies to Nissan CVTs and Hondas, which use a clutch pack instead of a torque converter.

Let's not forget about hearing. While driving, no crunching or grinding noises should be heard from under the hood from the gearbox side. In Qashqai, sound insulation is at a low level, so the engine compartment will be clearly audible.

Cruise control

If the car is equipped with this function, turn it on and look at the engine speed and speed. They should not twitch or remain static.

Change the speed reference. The tachometer and speedometer should change smoothly, either increase slightly or decrease. Again, jerking and kicking are not allowed.

Typical breakdowns

In most cases, the variator retires when the life of its main rubbing elements expires: belt + cones. This usually happens according to the following scenario. The belt slips, the surfaces are ground down, then the resulting chips rush through the channels and destroy everything in its path: the oil pump, bearings, pressure reducing valve, valve body, torque converter, etc., which forces the belt to slip even more.

Seizures on cones

Another common problem is overheating. Usually everything is not so bad, since the box monitors the oil temperature and warns the driver that the speed needs to be reduced. Another thing is that not everyone does what is required.

There are, of course, private problems such as failure of only the pump or only the cone bearings, but less frequently. Usually it's a matter of chips, and you know where the chips come from. It is worth understanding that any “disease” always progresses until the machine goes into emergency mode and is immobilized.

Jatco variator oil pump

The worst thing to fear is a broken belt. Usually, after this, almost all components are severely damaged, including the transmission housing itself, and this means replacing the entire transmission.

Worn variator belt

Why is there a need to replace the belt?

Experts and ordinary motorists identify several main reasons why it is necessary to replace the CVT belt.

This is possible in the following cases:

• natural wear of the variator transmission belt;
• node damage;
• expiration of service life;
• ongoing gearbox repairs.

The belt cannot just start slipping. Yes, the option of purely natural wear and tear cannot be ruled out. But to do this, the car must travel a huge distance. Basically, there are reasons that lead to such difficulties in the operation of the variator.

1. Lack of lubricating oil. For CVT, a strictly special oil is used, which differs from the lubricant for automatic and manual transmissions. If there is not enough of it in the system, the belt may begin to slip. This causes the surface to wear out much more intensively.
2. Extreme driving conditions. CVT gearboxes do not like sudden acceleration and braking, slipping, or driving with trailers. If you violate all these rules and do not adhere to measured operating conditions, the belt will soon deform and stretch. As a result, slippage will occur.
3. Failure of the speed sensor. If it breaks down and stops working normally, the box goes into emergency mode. In this situation, the CVT belt will change its shape if hard braking is performed.
4. Impacts on the box when reversing. This usually occurs when hitting obstacles, including in reverse. This will most likely cause problems with the belt drive. It will have to be changed.

Usually it is the driver himself who becomes the main cause of malfunctions associated with the CVT belt.

Many drivers are accustomed to driving a car with classic mechanics or a standard torque converter automatic. But the situation with the variator is completely different. Here you have to develop different habits and adapt to new requirements.

Smooth ride

The next most common defect occurs in the form of jerking and jerking of the car. The responsibility lies with the pressure reducing valve located in the oil pump.

The latter begins to function when the engine starts. The pump is manufactured as a monolithic unit and in the event of a defect in the pressure relief valve, it must be completely replaced. During normal operation, the valve should move freely in a mating sleeve pressed into the pump housing. Constant contact of the valve working surface with abrasive particles of wear products falling on it leads to the formation of many longitudinal scratches. When worn, the valve begins to jam so much that subsequently it is difficult to pull it out even with pliers.

The result is abnormal pressure, leading to disruption of the coordinated operation of the pulleys. This causes the belt to slip. Timely contacting the service allows you to reduce financial costs. Minor damage to the cones can be corrected by grinding. The belt must be replaced.

The most famous CVT oil sold in car dealerships is the product from Nissan NS-2 in a two-liter tin. The container of the new issue is silver, the old one is painted blue. In no case should it be confused with the old, completely incompatible NS-1 oil, bottled in pink containers.

Extreme enthusiasts who are accustomed to pulling out a stuck car by rocking with instant alternate switching of the lever from position D to R and back run the risk of encountering another problem - unpleasant jolts during the process of switching from the “parking” position to D or R. In this mode, there is practically no pause when switching. between positions D and R, although ideally a complete stop of the car is required. As a result, increased wear of the coupling spline joints inside the planetary gear in contact with the friction discs occurs. The result is the need to replace the planetary gears.

Bearing wear

This is the most common defect in CVT cones. It manifests itself with a characteristic hum after a run of at least 50,000 km.

The belt is assembled from numerous plates interconnected by steel constrictions. With its side surfaces, with subtle oblique notches applied to improve adhesion, it comes into contact with the pulley cones. During operation, the notches wear out, which can ultimately lead to serious damage. Therefore, even the elimination of humming bearings should be accompanied by a preventive replacement of the belt, which guarantees the preservation of serviceable pulleys.

Bearing noise can also occur for several other reasons:

1. Poorly manufactured bearings.
2. Insufficient dynamic load capacity, as well as a low degree of bearing accuracy, lead to their overload and destruction.
3. Penetration of wear products (small powder-forming particles) onto working surfaces, leading to destruction of the latter. This may be due to a large amount of metal powder clogging oil filters and weakening the field of the magnet installed to collect it. In some cases, this problem can be solved by changing the oil more frequently (approximately every 30,000 - 50,000 km).

There is no consensus among manufacturers on this issue. For example, Mitsubishi strongly recommends changing the oil every 75,000 km, while Renault-Nissan only allows monitoring its level and condition during the warranty period (100,000 km).

CVT oil is marked with the abbreviation CVT. Every car manufacturer has such oil. The original composition from Nissan is produced under the symbol NS-2. Mitsubishi is promoting the DiaQueen CVT-J1. The analogue from Renault is known as ELFMATIC CVT. Honda produces HMMF and CVT-F, VAG produces ATF CVT. All these fluids are recommended specifically for CVTs. It is absolutely unacceptable to use oils intended for hydromechanical automatic transmissions.

The amount of oil required for filling is determined by the type of drive and power unit. For example, for a front-wheel drive Qashqai with a 2-liter engine not equipped with an oil cooler, approximately 4.2 liters are required. A couple of liters will “get stuck” between the transformer elements and the hydraulic system components, since it is impossible to pump out these “drops” using the standard draining procedure. To completely renew the filling, they use the replacement method, using an appropriate installation and three times the volume of working fluid.

Hearing test

The most common problem is wear of the cone bearings. At the same time, an unusual hum appears. As a rule, this happens when the mileage reaches 50,000 km. Replacing all 4 bearings with the necessary additions will cost about 35,000 rubles.

At the same time, wear of the notches on the steel belt plates can lead to extremely disastrous consequences on the road, so replacing the belt will not be superfluous during any rearrangement of bearings. This problem is often found in Nissan Qashqai models, sometimes in Nissan X-Trail, and in Mitsubishi Outlander this malfunction appears only after 150,000-200,000 km.

variator bearings RE0F10A (JF011E)

You should not delay replacing bearings - with high-quality sound insulation and lack of driver attention, they can break and the cone can burst.

But if they make noise, they make noise for different reasons. First of all, worn particles come into contact with the functional surface and thus negatively affect the rate of its destruction. They inevitably penetrate there, since barriers in the form of a pair of oil filters and a magnet are not enough to hold them.

At the same time, the life of bearings can be extended by changing the oil every 50,000, or better yet, every 30,000. But this conclusion is based only on some observations; many experts do not see the connection here. Some CVTs live quietly up to 100,000-120,000 km, while others, under the same conditions of use, become noisy after 50,000 km. This means the issue is the low quality of the bearings. And sometimes bearings cannot cope with their work and its volume and wear out because of this.

The oil pump starts working immediately when the engine starts. This is a single mechanism that requires replacement when the pressure reducing valve fails. Meanwhile, it is very difficult to get a damaged and neglected valve. To ensure that the oil does not overheat, a liquid heat exchanger is built in, eliminating high temperatures using coolant.

variator oil pump

When it comes to changing the oil, there is no consensus. For example, the Renault-Nissan concern advises to simply monitor the correct oil level up to 100,000 km (with a warranty), while Mitsubishi asks to change it upon reaching 75,000 km.

It should be noted that even special oil is made for CVTs - marked “CVT”. Nissan makes the NS-2, and Renault recommends the ELFMATIC CVT. Mitsubishi recommends the DiaQueen CVT-J1. The most popular oil among them is “NS-2”, sold in 4 liters. But in essence, all these oils have the same base. However, using regular automatic transmission oil in a CVT is unacceptable. Although there are some such variators, these are rather atypical examples.

The amount of oil is also calculated based on the engine needs and the type of drive. For example, a rear-wheel drive Nissan Qashqai with a 2-liter engine in the absence of an oil cooler will need approximately 4.2 liters. In addition, several liters are still in the hydraulic system and transformer - this oil cannot be drained, and to completely change the oil they use a special installation, and under such conditions, 2-3 times more oil is needed.

It is considered one of the most reliable, but it also has weaknesses.

5 main malfunctions of the Jatco JF011 variator 5 main malfunctions of the Jatco JF011 variator

CVT diagnostics

If the variator malfunctions, the electronic system reacts:

1. The ECU limits engine speed to 2000 so as not to overload the already faulty transmission;
2. The Service required icon lights up on the instrument panel;
3. When the oil overheats, the Slow down icon lights up;
4. Electronics can completely block the engine.

The cause of failures in the electronics can be not only a breakdown of the variator itself, but also a malfunction of adjacent components, primarily numerous sensors.

Signs of a faulty variator mechanics:

1. Jerks and shocks when changing gears;
2. Inability to change gear manually;
3. Box slipping;
4. Driving in neutral;
5. Noisy operation;
6. Its complete stop.

Video: “How to check the variator yourself”

What to do if the unit shows any “unhealthy symptom”? Carefully load your “swallow” onto a tow truck and take it for diagnostics. And then look at what exactly “fly” and how much it will cost: either using a scanner, or disassemble the box yourself and identify the breakdown.

The scanner will show error codes, which may be real breakdowns or wiring faults. You can check what exactly is wrong by thoughtfully analyzing each of them. Disassembling the variator will help identify purely mechanical faults. This way you can define:

1. Belt wear. In a good way, the belt should be changed every 100 thousand km, but people usually forget about it;
2. Presence of metal shavings in the crankcase. A sign of severe wear on the belt and pulleys;
3. Wear of pulley or differential bearings;
4. Worn oil pump pressure reducing valve.
5. All these malfunctions can be eliminated on your own.

Variations on the handle

So, with the general principles of changing the gear ratio everything should be clear, now it’s time to proceed to the mechanism of this change, that is, how to make the scooter’s variator pulleys move and move apart exactly when required. To do this, let’s immediately make a reservation that in a scooter variator it is customary to distinguish the driving pulley (located on the crankshaft) and the driven pulley (located on the clutch shaft). In the bowels of the drive pulley there are special cylindrical weights (sometimes also called rollers). These plastic-coated metal bushings are placed in special grooves in which they can move radially. If you move the weights in the drive pulley from the center outward, they will inevitably move the pulley cheeks together. In fact, of course, only one cheek of the variator pulley moves, but this is not important. When the pulley rotates, the weights, under the influence of centrifugal force, tend outward and, shifting the pulley cheeks, push the belt outward. The faster the pulley rotates, the stronger the centrifugal force acting on the weights, and the further outward the compressing pulley cheeks will push the belt. The driven pulley has no weights, but has a large spring that constantly tries to squeeze its jaws together and push the belt out. Like the driving pulley, the driven one has only one moving part - the external one (referred to in foreign literature as the torque driver). It is the torque driver that moves either outward, overcoming the resistance of the spring and allowing the belt to “fall” inside the pulley, or, conversely, inward, closer to the fixed part of the pulley. Thus, the change in the working radii of the scooter's variator pulleys always occurs synchronously. When the belt goes out in the driving pulley, then in the driven pulley, overcoming the resistance of the spring, the belt, on the contrary, moves inward, closer to the axis of the variator pulley.

For a more complete understanding of the process, let's see
how the scooter's variator behaves under different engine operating modes . At idle, the rotation speed of the variator drive pulley is minimal. Although a certain centrifugal force acts on the weights, it is not enough to pull the belt out. After all, this requires overcoming the resistance of the large spring of the driven pulley! But now the gas is open, the crankshaft speed jumps, and now the centrifugal force acting on the weights is already enough to push the variator belt in the drive pulley a little outward. Drive pulley coupling: cover; guide plate; coupling body; rollers. The gear ratio changes. The rotation speed of the driven pulley of the variator increases significantly, which forces the centrifugal clutch to operate. The scooter starts moving. The engine speed reaches its operating level, meanwhile the belt continues to move further and further outward in the drive pulley of the variator, and deeper in the driven pulley. That is, the speed remains unchanged, but the gear ratio gradually changes, making the scooter go faster and faster. This, by the way, hides one of the great advantages of the variator - acceleration occurs at constant speeds, so you can configure the entire system so that during acceleration the engine will operate at its maximum power (for example, this is impossible to achieve with a manual transmission). Finally, the belt reaches its maximum design radius in the drive pulley of the variator, and its minimum in the driven pulley. However, as a rule, it is possible to accelerate a little faster, but by increasing the speed of the scooter's engine, and not by increasing the transmission. When the throttle is closed while driving, the engine brakes the scooter for some time until the centrifugal clutch disengages. As soon as it is turned off, under the action of the large spring of the driven pulley, the belt returns to its original position, as when idling a scooter. But as a rule, the scooter’s clutch disengages only when it comes to an almost complete stop (10 - 25 km/h). By the way, about the scooter’s clutch. This device, although it performs independent functions, is very closely connected with the scooter’s variator itself: if the clutch does not work correctly, the variator will not work correctly, and vice versa. A scooter's centrifugal clutch is almost always three drum-type brake pads that are pushed outward by centrifugal force and engage the clutch drum. The clutch assembly itself is mounted on the driven pulley of the variator and rotates, but the clutch drum is on a shaft, which transmits torque to the rear wheel through a simple gearbox. Thus, in order to make the scooter move, you need to make the clutch drum rotate. This happens as soon as the driven pulley of the scooter's variator gains sufficient rotation speed so that the centrifugal force becomes large enough for the pads to overcome the elastic force of the clutch springs, which prevents their free movement outward. These same springs will “disengage” the clutch, squeezing the pads together when the rotation speed of the driven pulley drops below the critical level for the clutch to operate. As you can see, the system is simple. And it works almost flawlessly, reducing control of the power unit to twisting the throttle (hence, by the way, the name of one popular scooter magazine: Twist'n'go - “Twist and Ride!”). Which not least determined the current wave of popularity of scooters. This video shows the CVT in action. Shown in the best possible way.

What if you handle it with care?

This variator became the next link behind the very reliable units of the first generation (RE0F06A), which we did not see - of course, with the exception of those who brought right-hand drive cars from Japan. Its descendant, JF016, is now installed on many cars, and it is considered more capricious and unreliable.

With proper operation, the Jatco JF011 variator runs for a long time: problem-free runs of up to 180,000 km are known.

The main thing is not to overload the variator, change the working fluid every 45,000 km and contact specialists at the first sign of a malfunction. CVT repair is not a cheap operation. But usually it costs no more to repair it than a hydromechanical automatic machine.

Signs of trouble

Noise and rattle

The reason is wear of the bearings on which the cones rotate. And, even worse, wear of the seats of these bearings. Both low-quality bearings and a loose fit are a manufacturing defect. Sometimes it can be fixed under warranty. If the warranty has expired, only complete disassembly and troubleshooting will save you.

You shouldn’t delay repairs for a long time: wear products spread throughout the variator and damage all its components.

• Occurs after driving over 20,000 km
• Cost of repair: not less than 60,000 rubles (with restoration of the bearings by spraying).

Jerks during acceleration

They indicate instability of the control pressure. The pressure reducing valve is responsible for regulating the pressure created by the hydraulic pump. Metal shavings cause it to hang, and the pressure of the working fluid becomes unstable. But it controls the compression of the cones.

• Occurs after a mileage of 60,000 km (if the fluid is not changed on time and the driving style is aggressive).
• Repair cost: no less than 40,000 rubles, although the unit costs only 1,000 rubles. The fact is that the valve cannot be changed without disassembling the variator.

Switching to emergency mode

If significant deficiencies are detected, the control unit switches the variator to emergency mode. If after restarting the engine the car can be driven, then the reason is most likely a malfunction of the control electronics.

• Occurs after a mileage of 40,000 km
• Repair cost: up to 20,000 rubles.

Complete immobilization of the car

A situation when the variator suddenly stops transmitting torque: the engine roars, but the car does not move. The most likely cause is a broken steel belt. Here you need to call a tow truck.

• Occurs after a mileage of 80,000 km
• Repair cost: about 90,000 rubles.

Jerks in all modes

Bearing wear and problems with the pressure reduction valve gradually damage the belt and cones - the most expensive and important elements of the variator. Belt slippage caused by scuffing on the working surfaces is manifested by twitching in all driving modes. Repair of the variator in this case consists of replacing the cones and belt. Sometimes it is possible to grind the cones, but the belt will have to be replaced in any case.

• Occurs after a mileage of 40,000 km
• Repair cost: about 90,000 rubles.

Despite the fact that the first production cars equipped with CVTs appeared back in 1958, this type of automatic transmission became especially widespread in the late 80s, and was mainly used by Japanese automakers.

More and more automakers are choosing CVT or CVT (Continuously Variable Transmission) as automatic transmissions for their vehicles. The leaders in the production of CVTs in the world are several companies: Aisin and JATCO, both Japanese companies, the first belongs to Toyota Motor Corporation, the second Nissan Motor Co., Ltd. But you shouldn’t think that only the Japanese know a lot about CVTs. CVTs are also produced by Audi, Mercedes-Benz, Ford...

As with any other gearbox, the principle of a variator is to change the gear ratio of torque from the engine and redirect it to the wheels, but structurally it is a completely different unit. The CVT transmission does not have a specific number of gears, and for this reason it is often called a “continuously variable” automatic transmission.

Despite a number of advantages of the CVT, the owners of the first production cars equipped with such gearboxes were dissatisfied. In addition to some mechanical problems, they also encountered a number of operational limitations, such as the inability to tow a trailer for a long time, CVTs do not like fast acceleration and long slips, and cars with this type of transmission are very limited in raising engine power. All this can cause premature problems with the unit.

Now let's take a closer look at what the owner of a car with a CVT may encounter.

1. The first thing that owners of used Nissans and Subaru began to complain about was the wear of the cone shaft bearings. All this is accompanied by a hum, and can occur both at 50,000 km and at 100,000 km. Although the unit is repairable, it is better to rely on the factory warranty, since replacing all four bearings will be very expensive.

Shafts with bearings and belt

It is better not to delay the repair, since if the bearing is destroyed, the tapered shaft itself will also be destroyed. Also, when play forms on the shaft, the metal plates of the belt also suffer. This problem can be prevented by changing the CVT oil once every 50,000 km. The cost of changing the oil is also not cheap, and the transmission fluid itself is more expensive than ATF for a classic automatic transmission.

2. When changing the oil in the variator, you should strictly adhere to the manufacturer’s instructions and do not skimp on the original oil. Since the CVT is a complex mechanism, it is very demanding in terms of compliance with tolerances and standards. Otherwise, saving a couple thousand rubles can accelerate wear and tear and entail even more waste.

3. Since any transmission does not like high temperatures, heat exchangers are often installed on CVTs.

variator heat exchanger. Photo — drive2.ru Svyazist91

This device is a radiator, which includes transmission oil from the CVT, and through another channel, antifreeze from the internal combustion engine cooling system enters the heat exchanger. The first reason that the oil in your variator has risen above normal is most likely a clogged heat exchanger. It should be washed every two to three years. Overheating can also be caused by the fact that the transmission fluid has accumulated a lot of sludge and deposits and requires replacement. Overheating the oil in the box to a critical temperature will cause the variator to go into emergency mode and everything will return to normal only after the unit has cooled down.

Mitsubishi Outlander CVT overheating signal

4. Like a classic automatic transmission, a variator can “kick” as it is called. The reason very often lies in the oil pump pressure reducing valve. Due to its unstable operation or non-function, the oil pressure may constantly “jump” or not rise at all.

Oil pump

This problem can only be solved by replacing the valve, or the entire pump. In addition, the shafts may need to be ground, and the belt will most likely require replacement. The sooner you contact a specialist for repairs, the cheaper this repair will cost you, since operating a car with a faulty variator will simply aggravate the situation.

Like any complex mechanism, there are a number of conditions in the operation of a variator that must be met for its trouble-free operation. Very often, breakdowns are associated with improper operation or untimely maintenance, but nevertheless problems exist, and manufacturers try to fix them from year to year. Something is working out, something is not yet happening, but the trend of changing classic automatic transmissions to CVT has been visible for a long time, and I think that in the foreseeable future, more and more cars will be equipped with a CVT.

Which runs are critical?

In many ways, the reliability of a particular variator will depend more on driving style and conscientiousness of maintenance, however, some average values ​​can be tracked. For example, the Multitronic and Lineatronic “chain” transmissions made by Volkswagen and Subaru, respectively, have a good service life. The average service life of these boxes is about 250,000 km.

CVT Lineatronic

Japanese Aisin CVTs are running a little less, and are gradually taking over the Toyota model range, leaving a temporary right for the existence of traditional automatic transmissions only on heavy SUVs. The most popular version of Aisin K111 lasts approximately 230 tkm.

Aisin K111

Jatco (Nissan) products are the most popular in the world. Their CVTs have sold over a million copies and are installed on Nissan, Mitsubishi, Dodge, Peugeot, Citroen and some other brands. They are less resourceful. If we take their most popular version JF011E, then its latest modifications travel on average 180 tkm, but for its successor JF015E this mark has dropped to 150 tkm, although in terms of behavioral indicators this gearbox can be confused with a traditional automatic. It turned out something like “one step forward and two steps back.”

Belgian VT2 gearboxes installed on Chinese Geely cars finish the list with a modest figure of 100 tkm. Although, especially careful owners say that the CVT is not so bad if you don’t put too much stress on the transmission and change the oil on time.

It is also worth noting that the lifespan of the same variator installed on different models may differ depending on the manufacturer’s amendments. For example, the Jatco JF011E unit on the Mitsubishi Outlander 3 lasts much less than on the previous generation of Aulanders or in comparison with the same box on the Nissan Qashqai.

"Reference" values

We've just pointed out some imaginary problems, but what if we encounter a real problem? Let's take a look at the information that will help you identify these damages as soon as they show up on your doorstep. Here are some tables and diagrams that provide pressure characteristics, port locations and hydrodynamic studies, that is, all the relevant information you need to diagnose malfunctions is given.

As you can see, significantly higher pressure values ​​are involved here compared to conventional automatic transmissions. To measure pressure, use a pressure gauge with a minimum of 1,000 psi (7,000 kPa). You will also need a standard Jatco port adapter. If you don't have one, you can make one yourself by drilling out the center hole in the crankcase plug and then soldering 1/8″ tubing to it.

It is not difficult to determine the location of the ports for measuring pressure (Fig. 6). Most of the ports and the fill plug are located at the front, towards the radiator, just below the driveshaft speed sensor. They form a circle of four points, with the primary pulley pressure port in the center. The Reverse brake port is located near the shift shaft on top, and the secondary pulley port is located on the heat shield side. Attention: this configuration is relevant only for JF011E, the location of the ports on other variators is different. Refer to the appropriate reference guide for port locations on other models.

Replacing transmission fluid on a CVT

Every 15,000 km you need to check the fluid level in the gearbox. A dipstick is used to control the oil. To replace the transmission fluid, it is advisable to warm up the car and place it in an inspection hole. Access to the gearbox is opened, a container is placed under the drain plug where the used oil will drain (about 6 liters are drained). Finally, tighten the plug and add new transmission fluid through the top filler hole. The dipstick allows you to control the amount of added fuel.

DIA QUEEN CVTF-J2

Only the fluid recommended by the manufacturer is filled into the CVT box. For Jatco models, DIA QUEEN CVTF-J1 can be used. The timing of replacing the transmission fluid is directly dependent on what driving style the motorist adheres to and on what roads the trip takes place. The first replacement may be necessary at 60,000 km, however, with measured operation, adding new fluid can be done even after 90,000 km. It should be noted that the fuel changes along with the filter elements.

The CVT transmission ensures efficient reversing of the vehicle. For preventive purposes, before driving a crossover in winter, the car needs to be warmed up. In order for the gearbox to warm up well, the driver must, with the power unit turned on, press the brake pedal and activate the “D” / “R” transmission mode (forward / reverse). If you start driving with an unheated variator, this will be an indirect reason for the belt to start slipping.

Temperature mode of the variator

Temperature is a special characteristic of a continuously variable transmission. There is even a special self-diagnostic system that includes a temperature sensor. When it detects an increase in temperature, the variator is automatically switched to an emergency operation state, and a light comes on on the dashboard.

On some vehicles, in order to create the required oil temperature, in addition to the heat exchanger, an additional radiator is created in the engine compartment; it is located in front of the air conditioner condenser. The condenser tends to become contaminated with dust through the air ducts, which blocks its operation.

The main symptoms of too much dirt in the radiator are too much temperature at high speeds. Therefore, it is necessary to flush the radiator at least once every 2-3 years. The best way to do this is to remove the bumper.

And it would be useful to install a protective mesh in the air ducts, since radiators are often simply destroyed due to various kinds of objects flying into them from the road. For example, as for Renault Coleos, the radiator from the variator is primarily exposed to air flow, and therefore is often damaged by stones and clogged with dirt. And this reduces the quality of radiator ventilation of the engine cooling system.

CVT radiator

There is a high probability that CVTs will become more common, since problems with them are no more common than with mechanics. That is why car companies are increasingly popularizing them, although they did not favor them before.

An example is the Toyota concern, which is famous for its reliability. They put a CVT in the RAV-4 and Corolla, and Subaru in the XV, Forester and Outback, although drivers who prefer this company like to drive at high speeds. And not so long ago there was an opinion that the variator was intended for low speeds.

But everything is changing.

Detection of defects by external manifestations

Many variator malfunctions can be identified by characteristic external manifestations, but such “diagnosis” has one significant drawback - the manifestation of different defects may be the same. This is reflected in the table below.

External manifestationProblems

There is no movement; weak dynamics (slippage)	· breakdown of the main clutch; · defective variator transmission; · torque converter problems; · breakdown of the electro-hydraulic system; · problems with the control module.
Push when changing neutral to D (R); intermittent movement	· breakdown of the pressure solenoid valve in the main line; · problems with the control module
The car is moving in neutral	· the gear selector is faulty; · problems with the control module; · defective wiring or connectors.
Manual gear shift does not function	· problems with the control module; ·damaged electrical wiring or connector contacts; The gear selector is faulty.

The most serious and materially costly defect of the above is the defect of the variator transmission. It occurs when the belt slips between the pulley cones with the simultaneous formation of scoring at the ends of the belt segments and the working surfaces of the cones. This problem can only be eliminated by complete replacement.

What causes a variator to break down?

The main cause of known malfunctions of CVTs is violation of basic operating rules:

• the oil or filter element was not replaced on time;
• use of low-quality oil;
• aggressive driving style;
• prolonged driving at maximum speed;
• sudden braking.

Additional causes of malfunctions can be various defects in structural components (defects, ill-conceived design, poor-quality connection), as well as natural physical wear and tear of the constituent elements, which manifests itself after 150,000 - 200,000 km.

CVT malfunctions can occur both in its electronic control module and in mechanical components.

Electronics defects

In the first case, detection of a specific breakdown is carried out using computer diagnostics. A diagnostic code is assigned to each defect. Thus it is easy to determine:

• problems with the electronic control module board;
• defects in the speed sensors of both pulleys, operating oil temperature, pressure in the main line or pulleys;
• malfunctions of the stepper motor, defects in the blocking valves of the hydraulic transformer and control of the operation of the planetary gearbox, solenoid valves for pressure in the main line and the driven pulley.

The probable cause of a defect in the electronics may also be a violation of the integrity of the electrical wiring or unreliable contact in the connector.

Mechanical problems

Computer diagnostic tools are not the only tools used to detect mechanical problems. In this case, it is necessary to approach the problem in a comprehensive manner and monitor the parameters of the working fluid, conduct road tests, read the diagnostic code, and clarify signs of malfunctions.

Maintainability and cost of maintenance

By the way, about repairs. Official dealers do not repair such boxes, they only replace them as an assembly, but there are plenty of specialized services that can carry out troubleshooting and replace only worn-out elements. Although, in general, the maintainability of the variator will directly depend on its popularity. The more such boxes are produced, the more components and specialists who can competently carry out the repair.

The easiest and cheapest option is for owners of cars with Jatco CVTs of almost all generations and modifications. The average cost of overhauling a box is 70 thousand rubles. depending on the extent of component wear. It is much cheaper to service the box in advance, without waiting for repairs, for example, change the oil every 30 tkm, and install a new belt at 130 tkm in order to save the cones and not clog the system with chips.

All CVTs have a magnet on the tray that collects chips. Based on the amount of accumulated material, you can roughly estimate the degree of wear.

Harmful factors

Before you buy a car with a CVT, you should understand for yourself some points about what the transmission does not like and this will definitely affect the reduction of the resource:

— aggressive driving;

— driving with an unheated gearbox;

— monotonous movements in traffic jams;

— fast driving on the highway (in this mode it heats up the most);

— towing another car or trailer.

— wheel slipping with a sharp “hooking” on the hard surface.

In short, the variator is bad because it cannot tolerate sudden and monotonous loads and high torque. It is logical to assume that the mass of the car also plays a big role. The greater the weight of the machine, the greater the load on the rubbing parts. However, this is not always the case. Often large cars with torque engines are equipped with more durable chain CVTs, such as the Infiniti JX, Nissan Murano and Nissan Teana with a 3.5 liter engine.

This raises a logical question. Isn't the variator asking too much from us? Traditional machines aren't as flimsy. Choose. Just keep in mind that the continuously variable transmission will charge you for efficiency and full implementation of engine torque.

Buying a used car with a CVT is the most dangerous, since it is impossible to check the remaining life of the variator using the in-place method; you can only rely on the fact that the previous owner drove carefully and maintained it properly. There are, of course, ways to check the variator yourself. But no one will give guarantees. Even official dealers rely on the fact that if the car drives without incident, there are no errors, then the gearbox is working. You will have to live either in hope or in anticipation. Confidence in the future is not for CVT owners.

Design and principle of operation of the variator

So, the variator design consists of two pulleys with variable diameters connected by a belt drive. When using the design, there are no steps, but instead there are two cones that face each other. When accelerating a car, the shaft speed is held at a certain point. Accordingly, the engine does not spin up in every gear, as happens with parts more familiar to motorists.

As for interaction with oil, there is a heat exchanger for cooling it, as well as two filters that clean the oil before entering the engine. Moreover, one filter is installed quite close, and the second is already inside the structure itself, making it more difficult to get to.

In general, car models with a CVT are of interest to designers, since CVTs allow you to smoothly change the gear ratio. This system fully realizes the traction capabilities of the engine.

CVTs are very different from the gears familiar to car enthusiasts, which is why few people still agree to buy cars with this part. Meanwhile, cars with CVTs are gaining popularity around the world, because some have already appreciated the benefits of using this part in the design of the car. Most cars with CVTs are Japanese models, but there are others, for example, Renault, Peugeot, Jeep, etc. The most popular model among CVTs is the JF011E from the Japanese. CVTs from this company are used in their production by manufacturers of the above brands, as well as Mitsubishi, Suzuki and even Toyota.

How often should you change the coolant in your car?

One of the most harmless troubles with a variator manifests itself as follows. For no reason at all, at a fairly high speed, the transmission overheating icon suddenly lights up on the dashboard and the car tries to stop and cool down. This most likely means that the oil cooling radiator in the box is clogged with dirt and has stopped performing its functions effectively. Usually it is located at the bottom in front of the engine compartment and all dust, insects, poplar fluff, etc. are pressed into it by the incoming air flow. The easiest way to “treat” this is by washing it. To prevent such a problem, it is enough to make it a rule to wash all the radiators in your car at least once a year (or better yet, twice).

Cone bearings are more likely to suffer from metal shavings than from other causes. Statistically, the Nissan Qashqai has the “weakest” bearings, but the Nissan X-Trail shows greater durability;

1. In Subaru, the bearings are structurally integral with the cones, which significantly increases the cost of repairs, the price is about $400 for a normal brand. But it’s still more profitable than a new gearbox;
2. Replacing the belt (chain) is done once every 100 thousand km. The estimated price of a new part can vary: from $50 for a budget brand to 300-400 or more for an original (for example, Honda or Toyota);
3. The oil pump valve is inexpensive, 10-20 dollars, but removal, disassembly and replacement will take quite a lot of time;
4. A valve body (for example, on a Nissan Teana or Murano) starts at $300. However, hydraulic units rarely fail;
5. And finally, oil filters are cheap consumables, costing 10-30 dollars apiece, and not changing them is simply a crime against your car.

Let's sum it up

As you can see, close cooperation between Mitsubishi and one of the world's largest manufacturers, Jatco, made it possible to install on the Outlander first the fairly reliable JF011E gearbox, and later the Jatco CVT 8.

As a result, the CVT 8, along with the latest X-Tronic CVTs, clearly demonstrates that a CVT can be quite reliable and has a long service life, and can also successfully compete with traditional automatic transmissions and robotic gearboxes.

As a result, the CVT transmission can easily cover 200 thousand km. and more. The main thing is to follow the operating rules, promptly change the oil in the variator, and also monitor the condition of the CVT belt. Finally, we note that if we compare a modern CVT and maintenance-free automatic transmissions, the service life of these transmissions today is at approximately the same level.

Do-it-yourself variator box repair

When disassembling the variator, one of the necessary tools will be... a smartphone. So that after the repair there are no “extra” spare parts left, you will have to photograph each stage of disassembly before the next part is removed. Wires - until disconnected, bolts - until unscrewed. Place the removed parts on the table in order of disassembly.

The procedure for disassembling the variator for DIY repairs:

1. Remove the cover. First the first part, then take out the shaft and remove the second part, take out the gears that are under it;
2. Remove the oil pump. First, unscrew the screws that secure its housing, then remove the pump gear, chain, remove the cover and remove the pump shaft;
3. Remove the cover from the back of the variator, tighten the belt with clamps and remove it along with the pulleys. Remove the clamps from the belt and remove it from the pulleys.

Replacing the belt yourself

If characteristic signs of wear and slipping of the belt on the variator appear, it is unlikely that it will be possible to do without replacement. This is not to say that the procedure is very simple. But some car owners successfully do it themselves. To replace a part, you must adhere to certain rules and recommendations.

Slippage, which is uncharacteristic of a CVT, usually ends with a single solution. This is an element replacement. To prevent the belt from slipping in the future, it is recommended to install a high-quality spare part that meets the requirements and design features of the box, and adhere to the key operating rules.

Self-replacement usually requires the use of the following tools:

• hammer;
• impact screwdriver;
• 6-8 clamps;
• keys 10, 11 and 14 sizes;
• wide table;
• camera or phone with a camera.

Such measures will help you avoid getting confused during reassembly and perform the installation as competently and accurately as possible.

The attachments are first removed, the old transmission oil is drained, and the gearbox housing and engine block are disconnected. The unit is removed and placed on a flat, spacious table.

Also, all components should be washed, cleaned and dried. This simplifies condition diagnosis and allows you to quickly detect damaged gearbox parts.

To replace the CVT drive belt, follow the following sequence of actions:

First, the fastening bolts of the box cover are unscrewed. The cover should be pryed off with a flat screwdriver and carefully removed. In this case, you need to remove the helical gear. Place these components in a separate plastic container and label them. The box is turned over, the shaft and a fragment of the variator housing are removed. The bolts should be unscrewed with a suitable size wrench. The cover must be consistently tapped with a hammer around the perimeter, which will then allow it to be removed. A pair of gears is removed. One by one, the variator parts are folded into separate containers

It is important not to confuse the components or mix them together. The pump mounting screws are unscrewed, the chain and gear are removed. Now you can remove the oil pump cover without any obstacles. The next step is to remove the shaft

After this, one part of the box is ready for repair. The box is turned over and the mounting bolts holding the lid are unscrewed. Using a screwdriver, carefully press the lid off and remove it. You have access to two shafts and a belt. The belt must be carefully pulled from its seat at several points using plastic clamps. This will prevent the element from breaking during dismantling. The pulleys are gradually removed and the belt is removed. Make sure that no debris or dirt gets into the openings. Place the pulleys on the table and pull one of them firmly, which will release the belt itself. Install a new belt and reassemble in reverse order.

The work is not easy, quite delicate, requiring strict consistency and extreme concentration from the master.

Because of this, many are hesitant to undertake replacing the CVT belt with their own hands, but entrust this procedure to specialists. Car service services cost money, and you will have to pay not only for the part itself, but also for the work performed.

Thermal mode

The temperature regime in CVTs should be observed especially carefully. This function is assigned to the self-diagnosis system and is carried out using a temperature sensor. If the limit value is exceeded, a fault signal lights up on the dashboard with the simultaneous transition of the variator to an emergency state.

In order to ensure optimal oil temperature, on most cars, in addition to the main heat exchanger, another radiator is connected. It is mounted in the front area of ​​the engine compartment up to the climate system condenser. Through the air ducts located in the bumper, it is often clogged with various debris - poplar fluff, leaves, dirt, gravel, midges, etc. The first manifestation of its critical contamination is severe overheating when traveling at high speeds. Once every two years it is necessary to clean and wash it very thoroughly. It's best to have the bumper disconnected. It is also recommended to cover the external entrances of the air ducts with protective nets, since the radiator is susceptible to damage from anything that flies from under the wheels.

According to the collected statistical data, failures of variators occur no more often than failures of hydromechanical units. Even the most cautious manufacturers, who were previously quite skeptical about the reliability of CVTs, began to use them in the power units of their popular models. For example, Toyota - on the restyled RAV4, Subaru - on Forester, XV and Outback. The owners of this brand can hardly be called slow drivers. Constant driving over rough terrain and powerful accelerations were recently considered unacceptable for the operation of CVTs. It seems that times are changing, so the prospects are brighter for them.

Sources

• https://autolirika.ru/pokupka-i-prodazha/kak-proverit-variator.html
• https://autotorque.ru/stati/chem-ploh-variator-sroki-sluzhby-osnovnye-polomki/
• https://autoleek.ru/korobka-peredach/variator/neispravnosti-variatora.html
• https://www.zr.ru/content/articles/927571-variator-jatco-jf011-nadezhnyj/
• https://AvtoStandart-m24.ru/avtomobili-drugoe/priznaki-neispravnosti-variatora.html
• https://autofeel.ru/obsluzhivanie_avtomobilja/2015/11/11/variator.html
• https://www.avtovzglyad.ru/sovety/ekspluataciya/2016-04-27-chem-boleet-variator/