Why the reverse gear on the VAZ-2109 does not engage and what to do. Reverse gear of VAZ 2109 does not engage: causes and repairs

01/25/2022 7,424 Transmission

Author: Victor

The situation when reverse gear does not engage on a VAZ 2109 is one of the most common problems with this car model. In addition, the VAZ 2108/09/099 “Samara” and VAZ 2113/14/15 “Samara-2” cars were equipped with the same type of gearbox (gearbox), so this transmission malfunction is typical not only for “Nines”.

Often, an attempt to engage a gear is accompanied by a strong crunch of gears, and if the gear is able to be engaged, the gearbox makes noise when moving in reverse. Other owners are faced with a situation where the gear shift lever moves forward all the way, but reverse gear does not work. At the same time, there are no complaints about shifting forward gears.

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Causes

The reasons why reverse gear engagement is poor or difficult may be as follows:

loosening of the fastening clamp of the rocker, due to which the length of the rod is not enough to fully engage the gear;
jamming of the reverse speed lock;
spring breakage and debris getting into the guide grooves of the gear selection mechanism;
spontaneous loosening of the selection mechanism mounting bolts;
the clamp bolt is cut off;
wear of the clutch disc and release bearing;
incorrect adjustment of the clutch and clutch pedal;
low oil level in the box or the need to replace it.

Clutch

When the clutch discs wear out, the pedal moves up and its position becomes higher than the others. In this case, when turned on, a crunching sound may be heard and the lever does not move, as if it is resting against an obstacle. You should not force the assembly, as this can lead to more serious damage - the gears will fly.

It is typical for such wear that the clutch pedal falls to the floor and you can hear from drivers that the VAZ 2109 does not engage the gears. Usually this applies to all gears, but only first and reverse can fail.

You can check by removing the rubber plug. The destroyed disc leaves fibers that look like tangled strands of hair. If such a phenomenon occurs, then a new clutch disc should be installed.

Due to constant loads, the cable stretches and must be periodically adjusted and tightened. In this case, the VAZ 21093 does not engage the first and second gears, and the rear may also fail. To fix the breakdown, you need to drive into the pit and tighten the cable. If it is worn out, replace it immediately. You can do this yourself.

A similar breakdown can also manifest itself in the failure of the gears to engage while the engine is running. Sliding along the splines is limited and fixation does not occur.

Tough: how to break manual transmission gears, and what it entails

The gearbox is one of the most important components of a car, but, paradoxically, it is often one of the most ignored. The engine oil is changed every 10 thousand, they take care of the cleanliness of the oil filter, monitor the operating temperature, oil pressure... In a manual transmission, the oil sometimes lasts for hundreds of thousands of kilometers, and the style of gear shifting and clutch operation adds problems to the box. The result can be quite predictable - so a manual gearbox from a Skoda Octavia came to our workbench, from which, according to the owner, “some kind of crunching noise was heard” when engaging first gear.

Gearbox: why and how

We will not analyze the structure of a manual transmission in detail: we have already talked about it. However, let’s go over the top to understand the processes that influence our repairs.

And so, globally, a gearbox is needed in order to transmit torque and power from the engine in a variable speed range. To change this range, pairs of gears with different gear ratios are used - it is thanks to them that those one and a half thousand revolutions will “turn” into several dozen revolutions of the drive wheels with a simultaneous increase in torque. The principle is similar to a bicycle: start off on a small sprocket, accelerate to 40 km/h - and switch to the next pair of gears with a smaller gear ratio to go faster. There can be 4 or 5 such shifts - modern manual transmissions are usually five or six speed.

The transmission of torque to the gearbox occurs directly by the meshing of these same gears. Gears are located on shafts - there are two-shaft and three-shaft gearboxes. The former have a primary (drive) and secondary (driven) shaft, while the latter transmit torque from the primary shaft to the secondary through an additional, intermediate one. The gears located on the shafts are in constant mesh, but all pairs, except the one selected as working at a particular moment, rotate freely. To select a pair - that is, to engage one or another gear by rigidly connecting the gear and the driven shaft - they came up with a special coupling and called it a synchronizer - we will talk more about the design and problems of synchronizers in the next material. Operating the gear shift lever from the passenger compartment, you connect one or another gear to the driven shaft through the shift forks and synchronizers and finally transmit torque from the engine to it (and therefore to the wheels).

Breakdowns and diagnostics

In general, anything in a gearbox can fail and wear out - and fixing it, as we know, can be very expensive and difficult. At the same time, the manual transmission is much more “secretive” than the engine: sometimes you can find out about a serious breakdown only after opening it. Therefore, when driving and changing gears, you must always listen to all sounds coming from the gearbox - and visit a service center when the first concerns arise.

Having excluded the clutch from the diagnostic list (we will also talk about it separately), you can only hear crunching or knocking noises from the box, and see only the lever randomly returning from the working position to neutral (in other words, “the gear flies out”). The latter is usually due to loose clamps or problems with the synchronizer. In the first case, this is wear of the synchronizers, excessive wear of the shaft bearings or breakage of the gear teeth. And it’s gears that we’ll talk about today.

They have several potential problems: excessive tooth wear, chipped or broken teeth, worn gear needle bearings, or worn circlips that can cause the gear bushings to become misaligned. In general, chipping or damage to teeth is a fairly rare occurrence, since they are designed with a large margin of safety. But it also happens that the box is simply overloaded, the clutch does not slip - and the teeth cannot withstand it.

This can also happen if the box overheats - for example, due to incorrectly selected transmission oil or due to its low level. Particular attention should be paid to the manual transmission in winter, in severe frosts. The oil in the transmission crankcase turns into something resembling honey, so you shouldn’t start driving right away - it’s advisable to stand a little and wait until the oil warms up at least a little. You can feel and understand this by the easier movement of the lever from position to position.

Returning to the diagnosis of the manual transmission, let’s remember the sounds coming from it. The knocking or crunching noise can be either constant or only appear when changing gears. In the first case, this most likely means a global disaster - the gears are destroyed or the shaft bearings have come to an end. Although this is rare, it does happen. If the knock is heard only when switching, then there is a possibility that this is either wear of the synchronizers or the notorious shaft bearings.

You can try to find out this while driving by shifting the box to the next gear with double clutch release: having squeezed the clutch, move the lever to neutral, release the clutch, squeeze it again and, engaging the next gear, release it. If during this “dance” the knocking noise disappears, then there is a high probability of excessive wear of the synchronizer.

We repair the gearbox

So, today on the “operating table” is a manual gearbox 02J produced by the Volkswagen concern, which was installed on the Skoda Octavia. According to the owner, the only problem was some kind of knocking noise when driving in first gear. The knocking was annoying, so the box was brought in for “treatment.”

The box was delivered separately from the car; our master did not drain the oil, and therefore did not see its condition. Having prepared the tools and, to the best of our ability and capabilities, cleaned the manual transmission housing from dirt, dust and other foreign objects, we began disassembling.

After unscrewing the mounting bolts, we removed the rear cover of the gearbox housing, under which the 5th gear gears are located. At the same time, the master gave the first assessment of the condition of the oil. This assessment was expressed in a wrinkled grimace, which gave the owner the first reason to get excited.

How to adjust the link?

You should drive the car onto a lift, pit or overpass. It is not recommended to carry out the procedure alone; you will need an assistant to switch the lever. You must proceed as follows:

Crawl under the bottom, loosen the clamp located on the gearbox rod and remove the drive from the rod.
Pull off the boot or remove this part altogether, unscrew the screw on the cardan.
Use a hammer to carefully knock down the cardan shaft and remove the boot, if this was not done initially.
If necessary, replace the oil seal.
Installation is carried out similarly, but in reverse order.

After the above steps, you will need the help of a second person. He should sit behind the wheel, set the gearbox lever to neutral and tilt it slightly to the right. It should be held in this position until the universal joint clamp is properly tightened.

First gear does not engage when driving

Often, when you turn on first gear while the car is moving, it jams and does not work. There are no problems when starting to move from a place. Some “experts” even put forward the theory that you should only start moving from the first gear, and should not use it during maneuvers.

This problem occurs because the injectors do not have time to equalize the torque of the gears, and the driver forcibly tries to connect them. The flywheel spins much faster than the drive shaft and the teeth can fly if the force is large.

Don't rush to press the lever. Bring it to neutral, push it lightly into first gear, and wait for the synchronizers to do their job and the gear to engage.

For old boxes there are instructions for switching with re-gas. When downshifting while driving, move the handle to neutral, step on the gas, increase the speed, and then smoothly change gear. This method is used by owners of preserved vintage cars, the price of which has recently increased significantly.

Troubleshooting

Many transmission malfunctions that cause the reverse gear to disappear or fall out can be eliminated without removing the unit from the car.

If the cause is a loosening of the bolt securing the clamp on the rod, then to correct the defect it is necessary:

Place the car on a lift.
Completely loosen the clamp nut.
Place the gearshift lever in the fully engaged reverse gear position.
Fully engage reverse gear at the gearbox using the shift rod on the crankcase.
Tighten the clamp mounting bolt.

Backstage adjustment

If tightening the clamp does not help get rid of the problem, then you need to check the condition of the shift drive parts. One of the reasons why the reverse gear does not engage may be a poorly adjusted rocker.

To make adjustments to the mechanism, you may need the following tools:

two wrenches with a size of 13 mm, preferably a socket design;
any wrench or 10 mm socket;
small hammer;
slotted screwdriver.

Since the cause of malfunction of the link can be wear of parts, spare parts may be needed:

universal joint of the rocker;
Sometimes the shift rod seal may need to be replaced.

Two people are required to adjust the rocker or replace parts of its drive. One person must change gears from the passenger compartment, and the second must adjust the travel of the shift rods.

The order of work is as follows:

Provide access to the bottom of the car by placing it on a pit or a lift.
Using a 13 mm wrench, loosen the clamp installed on the gear shift rod.
Remove the rod from the box rod.
Using a screwdriver, carefully remove the boot.
Using a 10 mm wrench, unscrew the fixing bolt on the cardan shaft.
Knock off the cardan shaft with light blows of a hammer. It is important not to damage the shaft.
Remove the universal joint seal boot.
If there is an oil leak, the sealing gland on the box rod must be replaced.
Install a new boot (or leave the old one if it is intact) and install the universal joint on the shaft.
Align the hole on the cardan with the notch on the shaft.
Tighten the 10 mm clamp and install the boot completely in place.
Install the rod on the cardan rod and adjust the gearshift lever travel.
The second person should sit in the driver's seat, set the gear shift lever to neutral, move it slightly to the right and hold it in that position.
After this, you need to tighten the 13 mm clamp nut.

Inspection and subsequent repair of the synchronizer

Removing the synchronizer involves removing the gearbox itself. This is hard work and quite dirty, so be prepared with gloves and rags. Since you have to remove the unit, it is worth carrying out cleaning work. Here's how to remove the gearbox synchronizer:

Remove the gearbox;
Remove the clutch cable bracket (by unscrewing the bolts and removing the cover);
Unscrew the fork mounting bolt;
Move the synchronizer clutch down;
Unscrew the nuts securing the primary and secondary shafts;
Lift the gear from the transmission, the fork and remove the synchronizer.

Please note that the algorithm may differ slightly depending on which transmission model is installed in your vehicle. Here it is worth turning to the manuals and looking for information on thematic forums. This kind of work is easiest to do in pairs rather than alone. Once the gearbox has been removed and you have been able to remove the synchronizer, it is worth starting to inspect and service it. Here's what to do:

Mark the position of the coupling with a marker or chalk relative to the hub, then carefully remove the coupling;
Wash the removed parts in kerosene;
Inspect the hub, coupling, splines. There should be no burrs or chips on the parts. Also pay attention to each of the crackers and springs;
Replace defective parts with new ones. Individual synchronizer components are rarely on sale, but they can be found at disassemblers. Every part should be lubricated with engine oil;
Assemble the synchronizer, taking into account the position of the mark. If everything matches, then the grooves on its coupling will immediately align with the grooves of the hub. It is better to insert crackers with balls using a screwdriver;
Install the synchronizer and assemble the gearbox.

As you can see, the work is quite complicated - you need to remember the location of each element of the synchronizer, and to be sure, even mark it with chalk or a marker. Be extremely careful. Since restoring a worn synchronizer requires skill and special tools, we do not recommend trying to troubleshoot it yourself. As for the mechanism that is not too worn out, it only needs to replace individual components, clean and apply lubricant. Otherwise, it does not require specific maintenance. Many craftsmen classify this mechanism as conditionally unrepairable, advising immediate replacement if problems arise with the gearbox.

Problems with reverse gear on automatic transmission

In practice, gearbox malfunctions associated with engaging reverse gear occur on both manual and automatic transmissions. "Automatic machines" have different designs. Robotic boxes are similar in design to “mechanics”. But the automatic transmission has its own list of breakdowns when it works hard or the reverse gear has disappeared.

The fluid level is below normal, or it is contaminated and has lost its working qualities. The automatic transmission device is sensitive to the quality of the lubricant and its level. Therefore, it is better to start finding out the cause by checking the transmission fluid. An excessive oil level also contributes to improper operation of the unit. The service life of the fluid is limited to a mileage of 60 thousand km, but sometimes it is necessary to change it more often, as the lubricant becomes cloudy and contaminated.
Wear of friction discs. The correct operation of reverse gear, as well as the “D” (drive) mode, depends on this. Worn clutches may prevent 3rd, 4th and reverse gears from engaging. In this case, eliminating the breakdown consists only of replacing the clutches.
The splines on the drive drum are cut off. The car can move forward, but it will be impossible to go backward.
Worn friction brake band. There is no reverse movement, but forward movement works.
The brake band piston cuffs are torn or worn. This will only be noticeable when you engage reverse.
Control solenoids or hydraulic units are jammed.

Sometimes the lack of communication between the torque converter and the oil pump gear also affects the reverse operation.

How to repair a VAZ 2109 gearbox?

Second gear is not detected.

When you start the car, noise comes from the gearbox and you hear crunching noises.

the fifth gear or reverse gear has failed;
The release bearing or the input shaft bearing is faulty.

Any transmission fails.

When driving at 9, there is a hum, when I press the clutch the hum does not stop. What's humming, bearings?

Hello everyone, help me, on 09, speed 2 stuck and won’t let go, what should I do? but we already sorted it out, now it’s set to 3 speed again, what should I do?

Possibly a bearing. Soon he’s still walking freely along the shaft. The shaft must be together with the internal part of the bearing. spin, and he rotates freely in it. It is also likely that this is the reason for the rumble.

I have a similar situation. I went through the box twice. I changed all the bearings, but the noise never went away. I'm already starting to get used to it.

The situation is exactly like this, it’s like my car in the video. Most likely you need to make a mistake in 5th gear, the only question is how to check. But one idea has appeared, you can remove the 5th gear cover, open two nuts, remove the 5th gear gears, close the cover, add oil, and then everything will be clear. I’m thinking about doing this one of these days. Report the results.

I checked the gearbox twice, but the second speed doesn’t turn on, I don’t know what to do. Please tell me!

Do not remove the 3.4 gear synchronizer hub. What to do? I read somewhere that you just have to film. And she sits there like a cast woman.

Sergey, check the release and clutch

The rear one flies out, I can’t figure out what’s wrong

The speed slips due to wear of the synchronizer (teeth on bronze gears).

I have this problem: there are 2 washers on the secondary shaft, one is a little thicker, the other is thinner, can someone tell me - which one comes first in order during assembly?

the thin one is placed under the bearing, the thick one is on top, there is a bushing and a needle on it

Why does the second speed turn on poorly? The rest work well and don’t make noise.

The situation is this: you squeeze the clutch, the noise disappears, the reverse speed does not work as well, when driving the noise does not disappear, what could be the reasons?

The third and fourth gears are poorly engaged

Tell me. Impact at start, as if there were huge gaps between the gears. The grenades are ok, I replaced the airbags, I also changed the satellite axle along with them and the six-pole axle, I replaced the clutch assembly. They say: sampling of backlashes and the box on metal. Can the problem be solved somehow?

This situation occurred when there was a blow to the gearbox body of the VAZ 2109. The 2nd and 4th gears stopped turning on and the idle speed stopped. What could happen? With the car turned off, all gears are switched on

Help! There is no neutral gear, what's the fun?

The problem is this: 2nd gear slips out when you let off the gas on the VAZ 21101, what could it be? Can I change the gear shift rod lock balls?

I can’t turn on the rear, the lever on the shaft turns, what can I do?

Mikhail, this is a disease, this is synchronicity!

I switched from first gear to second and can’t turn it off, what could be wrong?

Release bearing or input shaft bearing. Check the reverse gear

In the VAZ 2109, the second gear shifts into gear all the time with a crunch, you can only turn it on slowly, what should you do about it? And the clutch began to disappear.

There is a noise in the transmission as if the high-speed sprockets are hitting each other when driving in neutral and when pressing the clutch, what could be?

At first the rear one turned on poorly, but now only the third and fourth ones turn on. What should I do?

Guys, I ran into this problem. 2nd speed went out, changed the primary and secondary shafts along with gears. Everything worked well until the gearbox was removed and the release was replaced. I collected everything, drove about 300 kilometers, and the noise started. It looked like it was on the release side, he figured it out okay. Tell me what this could be? And yet, the right CV joint begins to rotate at increased speeds.

There is no reverse gear, tell me what to do and how much does it cost?

We've gone through the gearbox and the gears won't turn on!

Second gear does not engage

How to change gearbox oil

If you need to change your oil, then first of all, buy it.
A four-speed gearbox will require three liters of transmission fluid. You will need to pour 3.3 liters into a five-speed gearbox. If you are changing the oil for the first time, then buy 80W-85 class fluid. It is perfect for use in the VAZ-2109 gearbox. Car owners prefer to purchase Lukoil brand products. The work of changing the oil in the box is carried out as follows:

Place the car on an overpass or over a pit, warm it up slightly so that the liquid is not viscous. Locate the oil drain plug on the bottom of the box.
The unit has a rubber cap that needs to be cleaned along with the breather. After cleaning these parts from dirt, return them to their place.
As soon as the preparatory work is completed, place the container, twist the plug with a wrench, and begin draining the transmission oil.
The waste liquid will drain completely within half an hour.
Screw on the plug, tighten it well, but do not strip the thread.
Under the hood, find the transmission dipstick and remove it. In place of the probe, stretch a hose, at the other end of which a regular watering can or funnel is installed. Pour transmission oil into the box through the hose. On older units, the fill plug is located next to the drain plug.

After the work is completed, check the lubricant level with a dipstick and take a control measurement after 2-3 days. If necessary, add oil; if it becomes critically low, inspect the box for leaks.

Characteristic

As we said earlier, a 4-speed transmission was also installed on the car. The assembly of the gearbox for the VAZ-2109 of this type did not last long. Therefore, it is now very difficult to meet “short-winged” cars with a 4-speed manual transmission. It's practically a rarity. 95 percent of the “nines” came with a more modern, 5-speed manual transmission. It was two-shaft, with synchronizers in all gears (except reverse). Structurally, this gearbox is combined with the main gear and differential. It differed from the 4-mortar in a different location of the crankcase ventilation pipe. It was located on the clutch housing (previously it was on the rear cover). A dipstick also appeared. But the gear ratios remained the same.

In Russia, these cars stopped being produced back in 2004. But you can still find spare parts for the VAZ-2109 gearbox in stores. Their price is quite reasonable. If necessary, you can buy a complete transmission for 5-6 thousand rubles.

Old gearbox oil or low level

If the car is not new, then who knows if the gearbox oil was changed and when? You need to change the oil and pray that something worse doesn't happen. If there is a leak, drop by drop a day and you may not notice how the oil leaks out of the box. As a rule, this happens through the gearbox gasket or shaft seals. Over time, the box reacts to this with increased noise, but you might not have noticed this either. Both changing the oil and replacing gaskets with seals is best done at a service station, or on your own if you have a “green” understanding of what you are doing.

Video

A video from the Garage channel demonstrates the removal of the switching mechanism on an already partially disassembled box.

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Extending the service life of gearboxes

You will be able to use your car for many years without going to car repair shops if you can follow basic recommendations. They will extend the service life of the gearbox, minimize possible problems, breakdowns and the need for repair work.

Transmission shaft assemblies

There are only two recommendations.

Always try to monitor the oil level in the gearbox. If it drops, be sure to top it up immediately, do not delay the procedure until later. When the oil becomes unusable, change it completely, rather than fill in the missing amount.
Avoid aggressive use, do not jerk the gears sharply, accelerate smoothly, and brake similarly. A simple caring attitude towards the gearbox will allow you to avoid wear and tear and numerous breakdowns.

As you can see, solving problems with checkpoints is not so easy. Therefore, the best option is to prevent their occurrence.

Big trouble

Sometimes the reason for poor gear shifting lies in a more serious problem than described above. We are talking about damage to the spring, which is present in any box. A piece of the spring gets stuck in the groove and prevents the gear from changing normally. In some cases, reverse gear disappears completely, and sometimes works intermittently.

The problem is quite serious, because you will have to go deep into the unit, and not every car owner can do this. It is better to contact a car service if the reverse gear on the VAZ 21099 is difficult to engage. The technician will conduct an inspection and decide on further actions. You can replace the spring or install a new gear shift mechanism assembly. The second option is more preferable, since a separate spring may soon break again.

There are several reasons why the reverse gear on a VAZ 21099 does not engage. The breakdown must be identified and repaired in a timely manner in order to prevent serious consequences.

A slightly worse option

Often, reverse gear is lost due to problems with the solenoids in the gear locking mechanism. This is how you should proceed for verification purposes.

Find the correct one in the fuse box, marked F21. He is 8th from the left; if it is burnt out, replace it;
Raise the cover on the gearshift knob. There is a connector that is connected to the switch, you need to carefully disconnect it;
The connector contacts are closed directly. If the missing gear appears, we change the switch, if not, we dig further;
The connector is removed from the solenoid and the voltage is measured. It should be 12 V, you can throw in a 5-watt light bulb to control it.

If everything is in order, things are worse than you thought - the cause has not been found. If there is no voltage, check the wires and look for an open.

Box nuances

The VAZ 2114 uses a five-speed manual gearbox. It is quite simple in design, which allows you to independently carry out preventive and repair work.

Device diagram

Experts recommend identifying a malfunction at the initial stage of its occurrence, since delaying means wasting even more time, effort and money.

Features of replacing transmission fluid

Transmission oil must be changed at regular intervals, usually every 15-20 thousand kilometers. However, it may exhaust its resource earlier. This can be determined using a probe. Take a piece of white cloth and use a dipstick to transfer a drop of oil onto it. It is necessary to change the lubricant in cases where a drop of oil:

colorless or has a black tint;
contains metal particles or grains of dust;
opaque and viscous;
sticky to the touch;
absorbs into fabric for a long time;
cloudy or foamy.

Most often, reverse gear is difficult to engage if the oil has become cloudy. This is a sure sign that it has entered the engine. If the problem is not detected in a timely manner, you will soon need to carry out a complete gearbox repair or even an expensive transmission replacement.

Recommendations from experts

Sometimes the driver is forced to drive a car with a faulty gearbox in order to get to the repair site. But how to turn on the speed if the clutch is faulty or the synchronizer is worn out?

If first gear does not work, you can carefully move away in second gear.
If difficulties arise when turning on the engine while the engine is running, you can do this with the engine stopped and then start it. But this method can only be used by experienced drivers, as it can damage the transmission.
Double squeezing and re-gasping. It is necessary to set the gearshift knob to the neutral position, then press the clutch pedal, and lightly press the gas (up to 2500 rpm according to the tachometer). After this, you need to slow down and disengage the clutch again, and then engage the gear. If this does not work, then you need to repeat all the operations again. While driving, experienced drivers know how to change gears without a clutch mechanism.
When engaging reverse, the lever may not reach all the way. Then you need to slightly release the clutch pedal, the gear will turn, the teeth will engage, and the handle will reach the end.
After pressing the pedal, it is recommended to wait 3 seconds and then engage reverse gear.
You can try turning on the reverse by first setting the handle to 4th, then to the rear.
Repeatedly squeezing the clutch and returning the gearshift lever to neutral sometimes also helps solve the problem.

If you have a mechanic

Gears shift poorly in a car with a manual transmission for three reasons. The first of these is a malfunction of the clutch when it does not completely disengage (drive). The first sign of this malfunction is that the reverse gear is engaged with a characteristic crash. The rear one reacts to this anomaly more noticeably than other gears, because it is the only one not equipped with a synchronizer.

The second reason is a defect in the gear selection mechanism of the gearbox. And finally, the third is excessive wear of the gearbox synchronizers.

There are also several clutch malfunctions in which manual transmission gears shift poorly:

Air in the clutch release hydraulic drive or fluid leakage from it. The malfunction is eliminated by replacing failed components of the hydraulic system and pumping it.
Worn or broken clutch release fork. The part requires replacement or repair.
Warping (runout greater than 0.5 mm) or too thick new driven disk.
Failure of the basket (temperature deformation of the pressure plate or its distortion).
Loss of mobility of the support bearing of the gearbox input shaft (at the end of the crankshaft to which the flywheel is attached).
Jamming of the clutch driven disc hub on the splines of the gearbox input shaft. To eliminate the defect, clean the splines of the gearbox hub and input shaft. It wouldn’t hurt to lubricate them a little with lithol.
There is too much free play in the clutch release fork. Its value needs to be clarified with the manufacturer, since it is slightly different for different cars. Until you find out the value of this parameter for your car, set it from 5 to 8 mm. Too little free play of the fork is also undesirable, as it leads to clutch slipping and increased wear of the release bearing.

Excessive wear of synchronizers mainly occurs in those gears that are engaged more often: these are usually first, second and third. The rear one is not included in this list because it does not have a synchronizer. When your gear shifts poorly, and you assume that the reason for this is wear of the synchronizers, firstly, you should only have difficulties with this while driving. Secondly, in this case it switches better if you use double squeeze.

For those who don’t know what double squeeze is. To shift to a higher gear: depress the clutch, engage neutral, release and depress the clutch again, engage the gear.

Backlash in the so-called “helicopter” is one of the reasons for unclear gear shifting

To switch to a lower gear: double squeezing must be combined with re-engaging, that is, when the clutch pedal is released and the gearbox is in neutral, you need to press and release the accelerator pedal. This is how gears are changed in cars that do not have synchronizers. If the gearbox shifts easier using double squeezing, then the culprit for poor gear shifting is most likely worn synchronizers.

Look for damage or check that it is adjusted correctly. Don't even think about the clutch and synchronizers.