We act independently: how to turn on the front axle on a UAZ

• Node purpose
• UAZ 469 transfer case
• Housing RK Drive mechanism
• Control mechanism

Models from the Ulyanovsk Automobile Plant are distinguished by their off-road capability. The UAZ transfer case improves the vehicle's cross-country ability and allows you to move on surfaces of varying quality. On the UAZ 469, the transfer case is switched on mechanically from inside the car.

Tips for motorists

UAZ cars belong to the class of SUVs and in most cases their owners are those people who, for some reason, have to drive off-road. Unfortunately, the build quality of these cars at the Ulyanovsk Automobile Plant is clearly poor. Therefore, problems with shifting gears may appear even during the warranty period of operation of this vehicle.

There are several reasons why gears on a UAZ stop turning on. Moreover, the culprit of such a malfunction will be not only the gearbox, but also the clutch, if its driven disk, when the clutch is disengaged, remains clamped between the flywheel and the pressure plate. This happens in the following cases:

• the hydraulic clutch drive is not tight, resulting in air getting into it; — uneven wear of the adjusting screws of the pull lever;
• biting of the release bearing due to lack of lubrication on that part of the surface of the glass along which it must move;
• the clutch release fork is bent;

The largest number of malfunctions that lead to failure to engage any speed on a UAZ vehicle are located in the gear shift mechanism located in the gearbox cover. During the operation of the car, wear occurs at the lower end of the gear shift lever and the fork grooves, with the help of which the synchronizer clutches move.

This leads to the rocker jumping out of the fork groove and making it impossible to engage the gear. For normal operation, the permissible size of the fork groove should not be more than 13.8 mm, and the spherical surface of the end of the gear lever should not be less than 12.5 mm. Otherwise, they must either be replaced or repaired by surfacing by welding followed by machining to the required dimensions.

If only one pair of gears does not engage, for example, third and fourth or first and second, then a possible cause of this malfunction may be a slight bent of the rod on which the third and fourth gear shift forks are located. A similar malfunction can be caused by wear of the rod clamps, as a result of which the rod may move slightly from the neutral position under the influence of vibration, since the clamp cannot hold it in this position. And then the shift lever, when trying to engage one of the gears located on this rod, cannot get into the groove of the fork, because it has also moved along with the rod.

How to check the correct adjustment of the UAZ Patriot axle.

To check the correct adjustment of the UAZ Patriot axle, it is not at all necessary to know how to adjust it.
Before you do anything, check the temperature of the axle after driving fast. If the bridge gets very hot, then we can definitely say that it, at a minimum, needs to be adjusted. If such a bridge is not repaired, then sooner or later it will jam. 1. Unscrew the cardan from the bridge. With the car raised, rotating the axle flange (the universal joint mounting point) by hand in both directions, you can feel the presence of broken teeth, assess the condition of the bearings and other problems. 2. After removing the bridge cover, check the condition of the teeth on the main gear and differential by rotating the bridge. There should be no cracks, wear, roughness in the contact patch, cuts or torn teeth. Assess the location of the contact patch. In the crankcase you can sometimes find the remains of destroyed adjusting rings and broken elements. The problems listed above actually exist. If everything is intact, then the bridge can be adjusted. If there are problems, then... 3. Check for transverse clearances in the bearings. If there are gaps, then the bridge must be adjusted before it jams. 4. Check that the final drive is properly engaged. To do this, paint the teeth of the main gear with paint from an aerosol can and, turning the bridge in both directions, determine the pattern of engagement marks. The following figure shows the correct location of the contact patch on the teeth of the final drive gears of the UAZ Patriot axle. The following photo shows an example of incorrect adjustment of the main pair and the presence of roughness at the contact points:

After adjusting the rear axle, there should be no axial play in the bearings of the main gear drive gear and in the bearings of the final drive differential. The axial clearance in the bearings of the bridge is the main reason for its noise and jamming due to the destruction of the teeth in the main pair. There are very few craftsmen who know how to correctly adjust the main pair of the bridge. Instructions on the Internet are not very helpful, since the process is iterative, requiring not only ability, but also experience. We specialize in drive axle alignment. People come to us from other cities on the recommendations of our clients to rebuild drive axles and gearboxes, including foreign cars. Drive axles, aluminum and UAZ tuning are our competitive advantage.

Change of oil

The UAZ Patriot transmission should be filled with the highest quality oil that you can afford.
Too little quality can leak through low-quality seals. Very often, in the rear axle, over time, due to moisture getting into it, the oil turns into a thick, non-flowing liquid. Simply changing the oil in such a bridge does not have the desired effect. If you are not sure, remove the axle and axle cover and clean the axle. Do not have any illusions - if the breathers are not removed, if you drove on water, if a lot of time has passed, etc., then there is no longer oil in the bridge. Moreover, the slurry is not in the gearbox, but closer to the hubs. Those. The rear axle wheel bearings are practically not lubricated.

Breathers. Exiting breathers into the engine compartment

We recommend that absolutely everyone do this modification, especially since the costs for it are relatively small.

Breathers on bridges must be brought into the engine compartment so that water does not get into the bridge under any circumstances. For this purpose, brake hoses and brake pipes are usually used. It is easier to use oil resistant hoses.

At the end of the tubes under the hood, a plastic fine fuel filter from the classics is installed so that dust does not get into the bridge. In this case, the end of the tube is bent down so that water does not get into the bridge even if the car goes into more water than the location of the end of the tubes.

On cars with a compressor, during extreme operation, they sometimes create excess air pressure in the transmission - as if they inflate the axles, gearbox and transfer case from the inside. This completely prevents water and dirt from getting inside and well lubricates the oil seals in areas of friction.

Sometimes an expansion tank with a balloon is installed at the end of the tube to create volume. In this case, the connection between the internal space of the bridge and the atmosphere is completely closed. As the volume of air in the bridge changes during heating and cooling, the balloon inflates or contracts.

If you have driven through a ford with a depth of more than 30 cm, then you should immediately (on the same day) change the oil in the transmission - these are the manufacturer’s instructions. Draw conclusions.

Node purpose

The UAZ 469 transfer case is used to engage all-wheel drive. The mechanism is two-stage. This allows you to double the speed range for forward and reverse movement. Reducing torque when driving off-road reduces wheel slip.

UAZ 469 has a constantly engaged rear axle. The front axle is pluggable. Its inclusion is provided by the manufacturer for driving on low-quality surfaces.

IMPORTANT: It is prohibited to use the vehicle with the front axle constantly engaged when driving on high-quality road surfaces. Failure to comply with this rule will result in damage to transfer case components or jamming of rotating parts.

Disassembling the steering knuckle without dismantling the bridge

To perform this operation, first disconnect the hub by unscrewing the 6 bolts. Then bend back the lock washer, unscrew the hub nuts and remove it with the wheel and drum. Further:

• disconnect the oil deflector by unscrewing 6 bolts;
• remove a couple of bolts on the steering knuckle, hang the brake shield on the spring;
• remove 6 bolts to disconnect the cover and the knuckle body;
• to remove it, unscrew the bolts and remove the o-rings;
• Unscrew the knuckle linings, remove the kingpins and remove the steering knuckle housing.

As you can see, it is quite possible to repair the front axle of a UAZ with your own hands. However, you need to have experience in carrying out such work and a good set of tools.

Source

UAZ 469 transfer case

The transfer case is rigidly mounted on the rear of the gearbox housing. The rear of the transfer case is equipped with a parking brake. It is made in the form of a drum and pads with friction linings.

When the parking brake is applied, the release device presses the shoes against the drum, blocking the rotation of the rear axle driveshaft. After releasing the parking brake lever, the pads move in the opposite direction under the action of power springs. You can also read about UAZ “Cargo”.

Repair of the most common faults

Restoring the bridge to operability is not very difficult: but it is required to be careful when performing operations. What “diseases” are most common?

Leak formation

Where the steering knuckle connects to the bridge, there is an oil seal - one of the weak points of the design in terms of lubricant leakage. The oil seal can leak oil not only due to wear, but also when the breather is clogged. If you add more lubricant than required, the result will be the same: a leak. There are two types of oil seals:

• rubber: inexpensive, but also short-lived;
• polyurethane: more expensive, have a long service life.

To replace a part, place the car on a level place and jack up the problem side, loosening the wheel nuts in advance. Further:

• remove the steering knuckle;
• clamp the part in a vice;
• pull out the oil seal by prying it with a flat screwdriver or other suitable tool;
• pull the oil seal out of the support cavity;
• Lubricate the seal before installation;
• press in the oil seal using a tube of the appropriate diameter.
• Installation is in the reverse order.

The most problematic place of the bridge

The mechanism began to hum

First of all, check the oil level. If it is normal, the bridge will have to be removed and disassembled. If the bridge hums constantly in any driving mode, the reasons may be as follows:

• incorrect setting or limiting service life of differential bearings;
• breakage (wear) of the axle shaft (its bearing);
• wear, damage, incorrect gear adjustment.

These bearings simply need to be replaced with new ones. If a humming noise appears during a sudden stop or acceleration, the reasons are as follows:

• incorrect clearance between the final drive gears;
• The final drive gear teeth do not mesh correctly.

In this case, you need to correctly adjust the gearing or replace defective parts. If the bridge hums when the UAZ enters a turn and moves in a straight line, the reasons may be the following:

• satellites rotate with great effort;
• abnormal operation of the axle gears in the differential;
• destruction, severe wear of the axle bearing;
• incorrect clearance between gears located in the differential.

To restore the functionality of the mechanism, adjust the clearances correctly and replace damaged, worn bearings. It is worth noting that the desired result when adjusting the gaps can only be achieved on a bench.

Wheel axial play

It occurs when the wheel bearings are incorrectly adjusted or when they completely fail, which is caused by over-tightening. As a result, the bearings become very hot, the smear liquefies and flows out. Algorithm of actions when performing the correct adjustment:

1. Jack up the wheel on the desired side;
2. Use a puller to remove the axle shaft;
3. Move the lock washer to the side and unscrew the lock nut;
4. Spin the wheel: if it rotates tightly, the reason may lie in jamming of the cuffs, contact of the drum and pads, etc.;
5. Tighten the adjusting nut. Do this gradually while spinning the wheel. Use the WRENCH;
6. Unscrew the nut about a third of a turn and install the lock washer. Tighten the nut and lock it;
7. Check how the wheel rotates: it should spin freely without sticking;
8. Replace the axle shaft, replace the bolts and tighten them.

You can finally check while moving. If the hub gets very hot, loosen the hub nut about 1/6 of a turn.

RK Corps

The transfer case housing consists of two parts. To prevent lubricant leakage at the joint, the parts are sealed with gaskets. Oil seals are installed on the shafts coming out of the sealed housing. They prevent lubricant from leaking out when the car is moving.

REFERENCE: Under load, the lubricant and parts of the lubricant heat up. To avoid breaking the seal of the housing, the manufacturer equipped it with a breathing valve. The device provides communication between the device cavity and the atmosphere.

Drive mechanism

The RK mechanism consists of:

• Rear axle shaft. Rigidly connected to the rear driveshaft of the car. Mounted on ball bearings. They allow the shaft to rotate freely;
• Front axle shaft. Drives the front driveshaft. Fastened with a nut;
• Intermediate shaft. Necessary for engaging the front axle or downshifting;
• Shift forks. Used to move gears when turning the front axle on/off and to downshift. The movement of the forks is carried out along specialized rods. Each fork is equipped with a locking mechanism that prevents spontaneous movement of the product along the rod.

Transfer case switching diagram for UAZ 469

The transfer mechanism is controlled remotely from inside the car. downshift or front axle engagement is forced. This is done using levers installed next to the manual gearbox control.

The front axle drive is controlled by the right lever (in the direction of travel of the vehicle). To turn on the drive, the driver moves the lever to the extreme forward position. To turn off, the lever moves in the opposite direction. The front axle is controlled when the clutch is disengaged.

The left lever is used to reduce torque transmission. The control has three fixed positions:

1. Straight. The lever is in the extreme forward position. In this case, the transfer case does not change the gear ratio from the gearbox;
2. Neutral. The lever is set to the central position. Torque is not transmitted to the driving axles of the vehicle;
3. Downward. The control is switched to the rearmost position. The transfer case mechanism reduces torque.

ATTENTION: The UAZ 469 transfer case switching diagram, which is shown above, is equipped with a lock against involuntary downshifting. The lock is made in the form of a ball retainer, which does not allow engaging a lower gear without the front axle drive.

Transfer case service

When operating a vehicle, it is necessary to regularly service the unit. For this:

• A visual inspection is carried out for lubricant leaks at the locations of gaskets and rubber seals;
• The fastening of the transfer case to the gearbox and the tightening of the propeller shaft bolts are checked;
• The lubricant of the product is changed.

The oil in the transfer case and gearbox is changed at the same time. Each car owner determines the frequency of replacement independently. The manufacturer recommends changing the oil every 35 - 45 thousand mileage.

REFERENCE: When regularly driving a car off-road, it is necessary to change the transmission oil more often. This is due to high loads and the possibility of water entering the crankcase of the mechanism when fording.

Problems and solutions

The box requires periodic inspection and service. The mechanism is reliable, unpretentious and tenacious, provided it is handled correctly.

Repair of UAZ “Hunter” gearbox:

IMPORTANT!: Hunter machines use four or five-speed gearboxes. Five-stage devices use a working fluid whose characteristics differ from the lubrication parameters of the transfer case; a mixture of these suspensions is not permissible. The working fluid of the four-speed gearbox and transfer case is identical, you can mix oils.

The process of changing the oil in the transfer case of UAZ 469

Before starting work, it is necessary to warm up the transmission. To do this, drive a car for 2 to 4 kilometers. When heated, the viscosity of the oil decreases and it will be easier to drain it from the crankcase.

Changing the oil in the UAZ 469 transfer case is carried out in a certain sequence:

• Place the vehicle on a pit, overpass or lift. Some motorists prefer to carry out the procedure while lying under the car on a specialized tray;
• Clean oil stains and dirt in the area of ​​the drain and filler holes. A metal brush is used;
• Remove the filler plug. Necessary to prevent the occurrence of a vacuum in the crankcase when draining liquid;
• Place a container to collect used lubricant under the drain hole. The container must have a volume sufficient to collect waste liquid. It is better to choose a vessel with a wide neck. A bucket or cut plastic canister will do;
• Remove the drain plug. To prevent the plug from falling into the waste oil container, it must be held firmly;
• Wait until the fluid drains completely from the crankcase;

• Clean the drain and filler plug from dirt and metal particles;
• Install the drain plug;
• Fill in new lubricant using specialized tools. Syringes or pumps are used;
• Install the filler plug.

REFERENCE: When carrying out the oil change procedure on a UAZ 469, it is recommended to check the functionality of the breathing valve (breather). Malfunction of the product can lead to depressurization of the crankcase.

After replacement, it is necessary to eliminate oil leaks formed during the work. A rag is used for this.

Safety precautions when performing work

To avoid injury when changing the oil in the transfer case, you must:

1. Install wheel chocks under the vehicle wheels. This will prevent the car from rolling spontaneously;
2. When dismantling the drain plug, it must be kept at a distance from the transfer case. Hot oil from the transfer case can cause burns if it comes into contact with the skin;
3. Personal protective equipment such as gloves and goggles should be used to protect eyes and skin.

From the above it follows that the UAZ 469 transfer case is necessary to improve off-road performance. The design of the RK allows you to connect the front axle and reduce the torque from the gearbox. For normal operation, the unit must be serviced regularly.

Site about off-road vehicles, SUVs, off-road vehicles

The helical transfer case began to be serially installed on UAZ-3162 Simbir cars. It is 80 percent unified with a spur transfer case, but at the same time contains eleven original parts. The main difference between a helical transfer case and a spur transfer case is the presence of helical gears instead of spur ones to transmit torque to the front axle of the car.

The use of helical gears in the design of the transfer case made it possible to reduce its overall noise level by 8-10 dBA compared to spur gears, but only in the front axle engagement mode. In low gear mode, the noise remained almost the same, since the drive gear for direct and downshift engagement and the reduction gear of the intermediate shaft remained spur-cut.

UAZ helical transfer case.

Mechanical, two-stage, with reduction and neutral gears, without center differential, with the ability to disable the front axle. The speedometer drive can be either 624 or 1000 rpm/kilometer. The downshift ratio remains the same - 1.94. The helical transfer case is designed for use with engines delivering a torque of up to 30 kgm, which is 60% higher than the previous capabilities of a spur gearbox.

The transfer case is attached with four bolts to the rear wall of the transmission housing and sealed with sealant. Centering of the transfer case relative to the gearbox is carried out along the outer race of the double-row bearing of the gearbox secondary shaft. A parking brake mechanism is installed on the rear of the box housing.

The helical transfer case consists of a cast-iron crankcase with a cover in which the drive and intermediate shafts, drive shafts of the front and rear axles with gears are mounted on bearings. The drive shaft for the transfer case is the splined end of the gearbox secondary shaft; it is installed in the transfer case drive gear.

The rear axle drive shaft is mounted coaxially with the drive shaft on two bearings. A worm gear for the speedometer drive is installed between the bearings. The intermediate shaft is made together with the intermediate gear of the reduction gear. The front axle drive shaft is manufactured together with a gear and installed in the lower part of the transfer case housing.

General diagram of the operation of the UAZ helical transfer case.

The principle diagram of the operation of the helical transfer case remains the same, but the algorithm and method of connecting the front axle have changed. The torque from the gearbox is supplied to the drive shaft of the transfer case. The driven shaft is permanently connected via a cardan transmission to the main gear of the rear axle.

When the front axle drive is engaged, the shafts are connected to each other not by the front axle engagement gear located on the intermediate shaft, as in a spur transfer case, but by a gear coupling, which connects the shaft and the drive gear to engage the front axle.

Features of the UAZ helical transfer case.

The helical transfer case has another feature, which is that the intermediate gear mounted on the intermediate shaft and the front axle drive gear constantly rotate in it. Regardless of whether the front axle is on or off, hubs - wheel couplings for connecting the front axle - are on or off.

Therefore, in everyday use, at certain times and especially in hot weather conditions, this creates additional noise from the transfer case, clearly visible in the car interior, even though both of these gears are helical.

Gear shift mechanism of helical transfer case UAZ.

The switching mechanism on cars of the UAZ-3162, UAZ Patriot and UAZ Hunter family is single-lever. One lever alternately engages the front axle, then neutral and downshift. The mechanism consists of two rods and two forks located in the transfer case housing cover. The forks slide on fixed rods and are equipped with ball detents. In cars with four and five-speed transmissions, the transfer case shift control lever and its handle are different.

Main design problems

It is better to install reinforced axle shafts on UAZ axles

A bridge is a complex structure, the failure of which causes the entire vehicle system to fail. Main malfunctions of the rear and front axles.

1. Defective teeth of the main pair.
2. Axle shaft defect.
3. Oil leak.
4. Bearing defect.
5. Washer wear.

For what reasons do these malfunctions occur? If the car is equipped with rear-wheel drive and the front axle is connected here, then wild rides on bumpy roads will lead to catastrophic consequences. The transmission fails first, followed by everything else. If you often use gear oil without taking into account the season, then do not expect good performance from your car.

If axial gaps occur in the bearings, all sorts of failures occur, so it is very important to periodically inspect all parts of the car to identify problems. If the pressure in the tires changes frequently, then their long operation will lead to the destruction of parts. Defects in the shaft, crosspieces and suspension bearings also lead to problems.

The main cause of most problems is wear of components or their poor quality. Strong overloads will not have a positive effect on the operation of the parts; still, take care of your car. Insufficient lubricant for parts is another cause of malfunctions. Incorrect adjustment of the front axle bearings will also lead to unpleasant consequences.

Axles from MTZ significantly increase wheel clearance

Tuning is a good thing, but only if it is carried out by real professionals. But quite often, unscrupulous specialists make gross mistakes, as a result of which the stroke and dimensions of the driveshaft completely do not coincide with the required parameters. The result is a serious breakdown and the need for almost major repairs.

Symptoms of structural failure.

1. The front axle on the UAZ, like the rear axle, begins to emit a characteristic sound.
2. At first the car is almost imperceptible, and then it begins to lose control more and more.
3. The driver notices that fuel consumption is higher than before.
4. Engine and transmission parts wear out quite quickly.
5. Wedge while moving. Note that this is the worst of the symptoms. This means that there is a gap between the bearings, which can lead to serious problems. The wedge is accompanied by noise and crackling. In this case, urgent repairs are necessary.

To prevent malfunctions, timely adjustment of the UAZ rear axle, and the front one too, is necessary.