Disassembling the gearbox and troubleshooting its parts VAZ 2170 Priora

How to troubleshoot the Lada Priora gearbox

The axle is installed in the gearbox block and is held in place by a spring pin. It serves to secure the reverse gear and operates under severe conditions of vibration and increased loads.

The gearbox is the most important component of a car's transmission. Lada Priora is equipped with two types of gearboxes - mechanical and robotic. During operation, the parts of the unit wear out. Repairing the gearbox in Priora is becoming a necessity. Drivers often restore the box's functionality with their own hands.

How the gearbox works on the Priora

A vehicle's transmission transmits power and torque from the engine to the drive wheels. The gearbox is its main element - it is a set of mechanisms enclosed in a separate housing that disconnects the transmission from the power unit and changes the speed of the car.

Original box "Priors"

The gearbox in the mechanical version is a multi-stage gearbox, the task of which is to change the speed at the driver’s command. The motor is disconnected by the clutch. It is this that turns off the torque and puts the engine and wheels into idle mode.

The Lada Priora 2170 has a 2-shaft 5-speed manual transmission. The main elements are located inside the housing (crankcase):

• Primary shaft with speed drive gears. The teeth of the forward gears are oblique, while the teeth of the rear gears are straight.
• A secondary shaft with a block of driven gears and an oil sump at the bottom. The gears of the two shafts are in constant mesh.
• A synchronizer consisting of locking rings, a coupling and crackers.
• A lever used to change gears.

Priora manual transmissions are reliable, durable, simply designed mechanisms; you can always find cheap spare parts for their repair.

Since 2014, Lada Priora began to be equipped with a robotic gearbox - manual transmission, often called an automatic transmission. But this is a mistake: the robot represents the same manual transmission, but controlled not by a person, but by an electronic unit (ECU) through automatic switches (actuators). Gear selection, gear shifting, clutch operation - everything happens without driver participation.

The modernized “mechanics” eliminated the need for a clutch pedal and gear shift lever. The place of the latter was taken by the selector knob.

The VAZ Priora gearbox has a huge resource - 200-250 thousand km on the speedometer. However, the roads and the driving style of the owners make their own adjustments. On a Priora, gearbox repairs have to be done at 60-80 thousand mileage.

What else has changed?

The starter was also moved. Now it is not parallel to the gearbox, but along the engine. Three-cone synchronizers were installed on the very first batches. However, after carrying out the calculations, it became clear that the double-cone ones are no worse, but their cost is cheaper and they can fully withstand the required torque (even with a reserve). In addition, these synchronizers made it possible to remove the problematic cone on the gears of the first and second gears. Previously, it was in contact with the synchronizer ring and required high precision in manufacturing. Now the set of rings creates two friction surfaces. This has improved the synchronization process, making it smoother and more efficient. To make the switching process easier, the cable-driven gearbox from AvtoVAZ received synchronizers with a reduced tooth bevel angle. The preload force has also been reduced.

Main malfunctions of manual transmission and manual transmission

Breaking a gearbox is a costly affair, the only justification for which is the natural wear and tear of parts.

Other reasons for node failure are caused by owner oversight:

• sporty and aggressive driving;
• low-quality gear oil;
• non-original spare parts used for replacement;
• ignoring maintenance deadlines.

You can significantly delay the repair time of the VAZ Priora gearbox if you follow simple rules for operating and maintaining the transmission.

You also need to know the common problems with the box.

• oil leaks;
• noise at neutral speed with the engine running, shifting one or more (as well as difficulty, crunching) gears;
• their sudden shutdown;
• box vibration.

External manifestations of malfunctions can be caused by many reasons: wear of the synchronizer, breakage of gears, defective bearings, clutch problems, failure of the box fastening.

The robotic gearbox has its own damage:

• the warning light on the instrument panel lights up;
• while moving, buzzing and howling appear;
• lubricant leaks;
• engine speed increases, but speed does not increase;
• clutch slips;
• there are jerks and jolts of the car in motion;
• The manual transmission spontaneously stops working and the car stops.

What changed?

There are changes, albeit minor ones. The volume of oil that is poured into the new transmission has changed. Compared to checkpoints of previous designs, it decreased by a third. In production versions, engineers decided to switch from mineral oil to semi-synthetic oil. It confidently retains its properties down to minus 42 degrees Celsius. This is very relevant only for a new cable-driven gearbox. The oil now does not need to be changed during the entire life of the vehicle. The box has become maintenance-free, like on foreign cars.

Diagnostic methods

Do not start the situation if you notice that the box is not working correctly. Carry out the diagnostics yourself:

• Check the oil level and condition.
• Listen to the engine at idle and while driving. As a rule, defects detected by ear can be eliminated by a simple repair of the Priora gearbox in a garage in a couple of hours.
• Check electrical wiring and line pressure.
• Carry out a parking Stell test by manipulating the levers (don't forget to secure the car's wheels with shoes).

In difficult cases, remove the unit completely, but only if you are confident in your knowledge. It is safer to take the car to a car service center, where there are stands, computer diagnostic equipment, special measuring instruments, machines and tools for repairs. There they will find defective components, determine the degree of their wear, and recommend the type of repair.

Types of gearbox repairs

The controllability of the car, and therefore the safety of the crew, depends on the operation of the gearbox.

After a competent troubleshooting at the service station, they will discuss with you the remaining service life of the unit and the feasibility of restoring the structure. Afterwards they will offer to repair the Lada Priora gearbox:

• capital (with complete disassembly of the unit);
• partial (without removing the installation from the machine).

The first option after comprehensive diagnostics and dismantling includes:

• GTR - torque converter bulkhead;
• hydraulic repair or replacement of its elements;
• maintenance of the electrical network and ECU;
• replacement of consumables.

After assembling, configuring and installing the unit in place, the rocker is adjusted and output diagnostics are carried out.

Situational repairs may include:

• restoration of shaft journals;
• cleaning of threaded connections (if necessary, restoration);
• cleaning nicks on splines;
• discarding and replacing shaft teeth;
• welding cracks on the body;
• elimination of play in the gear shift lever.

Made with German precision

When this concept was transferred from paper to a real exhibit, and the mechanism began to work correctly, the module went to Germany, to. The Germans brought the knot to fruition. The company has long been developing various transmission systems and manufacturing engines. German experts carefully looked at the development of Russian engineers and proposed the following. Using a 3D center plate instead of a locking spring return system would make more sense. The special spatial shape of this plate was calculated using computer programs and manufactured using high-precision equipment. This accuracy is due to the fact that a special locking ball moves along the plate. And it is the plate that regulates the effort when selecting and engaging gears. The characteristics that the new cable gearbox will have were selected using a simulation stand. The man sat down on a chair and switched on various gears. Automatic systems simulate shift patterns, lever forces and strokes. And just like that, in small steps, the Germans managed to find the optimal settings. With the help of a computer, parameters and a mathematical model were selected, according to which these plates would then be manufactured.

Repair stages

Start by preparing your garage workspace, tools and materials.

• workbench for disassembling the gearbox;
• flushing fluids;
• standard locksmith kit;
• keys and heads;
• capacity for mining;
• rags.

Take care of lighting, exhaust hood, work clothes, and protective equipment (gloves, goggles). Any repair of the Lada Priora gearbox is accompanied by an oil and filter change: buy them in advance.

Dismantling

Removing the box is easy:

1. Place the car over the inspection hole and disconnect the battery.
2. Drain the oil (this must be done before any intervention in the box).
3. Next, disconnect the starter and clutch.
4. Place a support under the motor.
5. Disengage the wheel drive.
6. Unscrew the mounting bolts and remove the box along with the clutch housing.

Opening

First, wash the box with Labomid-203. It is necessary to remove the lubricant level indicator. Next, disconnect in sequence:

• covers;
• synchronizer;
• drive gears.

Then remove the shafts and, if necessary, disassemble them.

Parts inspection and troubleshooting

Afterwards, inspect each part, noticing chips on the teeth, cracks on the cast iron body. The latter must be sealed using manual or semi-automatic arc welding: the hot method in special ovens in the garage is impossible.

Inspect bearings and shaft seats. You may need to learn the ironing method to properly prepare the inner surfaces for the bearings.

Discard unusable parts. Make a list according to which you will purchase new items.

Determining the causes of malfunctions

When the box is removed and disassembled, the reasons for its “whims” are revealed:

• If you have removed the unit because the car does not move in any gear, look for a clogged filter, check the oil level, pay attention to the friction discs and brake bands. The reason may lie in the gears of the oil pump and the cuffs in the pistons.
• When only reverse gear works, the culprit may be the valve body valve (VV). Or the o-rings are broken.
• The car slips on inclines - the forward clutch discs are worn out.
• The car only goes backwards - the solenoid in the cylinder head is jammed.
• The car slips when starting, but then the gearbox works normally - perhaps the shaft is slipping due to a broken spline in the valve body hub.

Defective parts of the secondary shaft.

The most common malfunction is, of course, clogged teeth:

Moreover, this most often occurs in second gear. This is the main reason for transmission failure. Naturally, nicks appear not only on the ring gear, but also on the coupling. Therefore, the clutch also requires replacement. You should also carefully inspect the hub. The hub is made of cast iron, sometimes cracks appear in it and then it collapses. Therefore, it is necessary to carefully examine it; if cracks appear, it must be replaced. As a rule, the hub goes into spare parts assembled with the coupling. There are two types of hubs on these shafts with a 1-2 gear clutch. Nowadays, as a rule, they install double-cone synchronizers and clutches with gears with fine teeth. And the first years after these boxes were released, they put them like those in the second photo. They have ordinary couplings (VAZ 2108) only the hubs and gears of 1-2 gears are original.

On all gears, it is necessary to check the gap between the synchronizer locking ring; at least 0.6 mm is allowed.

You should also carefully inspect the shaft journals and internal surfaces of the gears for scoring, and replace worn parts if necessary. It is better to replace the rear ball bearing 6305 regardless of condition.

Recommendations

Drivers have accumulated extensive experience in servicing and repairing gearboxes. A gearbox is a complex and important mechanism, especially for a unit with automatic shifting. The main advice is to be careful and attentive.

1. Keep an eye on the oil level.
2. Avoid sudden starts and accelerations.
3. Engage reverse gear after the vehicle has come to a complete stop.
4. Do not carry trailers on a car with a robotic gearbox, do not push start the car.
5. Follow the rules for towing your vehicle.
6. Don't skip maintenance.
7. Carry out a daily inspection of the unit, listen to the operation of the motor.

For self-diagnosis and repair you need special precision equipment. Knowledge and skills of dismantling and assembly are important. For example, how to correctly measure the gap between a pair of meshed gears. If you are not a professional car mechanic, it is better to entrust the box to service companies.

Source

Cable drive

At AvtoVAZ they decided to abandon the traction drive entirely, even despite the maximum simplicity and low cost of the system. Almost all automakers have long abandoned rods. A cable-driven gearbox was first introduced as an experiment at Samara. Then the components were purchased from Morse. However, that gearbox had a lower location of the shift mechanism, which made the use of cables quite problematic, frightening engineers and cost. The project was not closed, and the serial updated cable-driven gearbox appeared only recently.