Diagnosis of malfunctions of cardan transmission, rear axle, running gear, steering and brake system
(This section also mentions failures of other systems with similar symptoms. They are marked with *)
Cause of malfunction | Elimination Method |
Rattle when starting off | |
Wear of the spline connection of the front end of the cardan shaft with its flange or cardan joints (clatter), the fastening of the intermediate support to the bracket or the bracket to the body is loose (clunk) | Syringe the spline connections with SHRUS-4, Fiol-1 or Litol-24 grease. Replace worn cardan joints or cardan shaft assembly, tighten intermediate support fasteners |
The gap in the gears of the main gear is large, their teeth are worn out | Adjust the backlash in the meshing of the gears. Replace worn gears |
The gap in the engagement of the gears of the final drive is broken due to the unscrewing of the shank nut | Tighten the nut to the recommended torque, install a new spacer if necessary |
Breakage of the reaction rods of the rear suspension or their mounting brackets, play in silent blocks | Replace rods, weld brackets |
Loose wheel bolts | Tighten the bolts to the recommended torque |
Brake pads stuck or frozen to the drum | Not a malfunction. |
Detachment of the brake lining from the base of the shoe | Replace shoe (better at the same time all on the same axis) |
* Faulty clutch | |
* Lost elasticity or collapsed support of the power unit | Replace supports |
Noise when driving on a flat road | |
The bearings of the rear axle gearbox are worn out, their preload is violated, the landing is weakened (constant noise from the rear axle) | Replace worn bearings, spacer, adjust preload (see rear axle) |
The teeth of the final drive gears are worn, the side clearance in the engagement is broken, the teeth are scuffed: howl from the rear axle, decreasing or disappearing when the load is reduced (releasing the pedal «gas») | Replace worn gears, adjust backlash |
Loose fastening of the driven gear to the differential box (gear runout) | Tighten threaded connections (thread sealant can be used), worn gears replace (couple) |
Wear of bearings of semiaxes or bearings of naves of forward wheels | Replace bearings |
Worn center bearing | Replace bearing |
Drivetrain imbalance | Check that the circlips of the cross bearings are in place. Balance the driveline at the service station or replace |
Tires not designed for these operating conditions (on asphalt, all-terrain, studded tires, snow chains, etc. are used.) | Use tires according to their purpose |
High speed in corners | Slow down before turning. Adjust the angles of the front wheels, tire pressure |
Uneven wear or peeling of the tread, deformation of the tire, rim | Change wheel |
Wheel touches fender liner (especially on a loaded car) | Check and adjust the wheel alignment angles, replace deformed suspension parts, sagging springs. Do not overload the vehicle. Use only stock wheels |
Wheel bolts touch rear brake parts | Use bolts according to the thickness of the rim |
Brake parts touching the brake disc/drum | Disassemble the assembly, replace defective parts |
Loose wheel bolts | Tighten the bolts, if the wheel is deformed, replace the wheel |
Detachment of the brake lining from the base of the shoe | Replace shoe (better at the same time all on the same axis) |
* Malfunctions of the engine, clutch, gearbox | See relevant sections «Diagnostics» |
* Howl, whistle from trunk (cargo) on the roof | Slow down |
Knocks, squeaks when driving off-road | |
The car is overloaded | Do not overload the vehicle. Distribute the load evenly using the saloon |
Shock absorbers are faulty, their fasteners are loose, rubber cushions are worn out | Replace shock absorber (better both at the same time on the same axis), rubber cushions |
Destruction of the suspension buffer (front or back) or additional upper buffer (rear) | Replace Buffer/Buffers |
Suspension spring settling or failure | Replace spring (it is better to change both springs at once - left and right) |
Breakage of the reaction rods of the rear suspension or their mounting brackets, play in silent blocks | Replace rods, weld brackets |
The exhaust system is incorrectly mounted or deformed: its parts touch the road or the driveshaft | Replace the exhaust system or change the position of its parts (based on suspension travel) |
Front suspension ball joints worn or not lubricated | Measure ball joint wear (see Front suspension), make sure that the ball studs move freely. Put fresh SRB-4 grease in the covers (lower support can be syringed) |
Worn or destroyed silent blocks of the front suspension | Replace silent blocks |
Loose lower and/or upper arm axles | Tighten threaded connections |
Weak fastening of the front suspension beam to the side members of the body | Tighten threaded connections |
The fastening of the steering wheel on the shaft, the steering column to the bracket, the steering mechanism and the pendulum lever bracket to the body side members are loose | Tighten threaded connections |
Knocking in the steering mechanism: severe wear or destruction of the working surfaces of the worm and roller, pendulum arm bushings, engagement gap not adjusted, no oil in the steering gear housing | Replace worn parts, adjust the gap in the engagement of the roller and the worm, add oil |
Bent suspension components (control arms, stabilizer bar), tie rods. Loose suspension parts | Deformed parts straighten or replace. Tighten threaded connections |
Loose or missing exhaust system fastening straps, exhaust pipe clamp to bracket on gearbox | Install new belts |
* Lost elasticity or collapsed support of the power unit | Replace supports |
Loose fastening of the axle shaft and brake shield to the rear axle beam | Tighten threaded connections |
High tire pressure | Set normal pressure |
Noise or clicks in the rear axle when turning the car or when one of the drive wheels slips | |
Worn or broken teeth of satellites or side gears | Adjust the axial clearance of the side gears, replace badly worn or broken parts |
Knocking, creaking when turning the car | |
Loose wheel bolts | Tighten the bolts, if the wheel is deformed, replace the wheel |
Increased axial play of the wheel (severe wear on the front wheel bearings or loose hub nut) | Tighten the wheel hub nut, replace the bearing if necessary |
Wheel touches fender liner (especially on a loaded car) | Replace deformed suspension parts, sagging springs. Do not overload the vehicle. Use only stock wheels |
Suspension spring failure | Replace spring (it is better to change both suspension springs at once - left and right) |
Breakage of the reaction rods of the rear suspension or their mounting brackets, play in silent blocks | Replace rods, weld brackets |
Front suspension ball joints worn or not lubricated | Measure ball joint wear (see Front suspension), make sure that the ball studs move freely. Put fresh SRB-4 grease in the covers (lower support can be syringed) |
Worn or destroyed silent blocks of the front suspension | Replace silent blocks |
Loose lower and/or upper arm axles | Tighten threaded connections |
Weak fastening of the front suspension beam to the side members of the body | Tighten threaded connections |
The fastening of the steering column to the bracket, the steering mechanism and the bracket of the pendulum lever to the side members of the body have loosened | Tighten threaded connections |
Knocking in the steering mechanism: severe wear or destruction of the working surfaces of the worm and roller, bipod shaft bushings, engagement clearance not adjusted, no oil in the steering gear housing | Replace worn parts, adjust the gap in the engagement of the roller and the worm, add oil |
Bent suspension components (control arms, stabilizer bar), tie rods | Deformed parts straighten or replace |
Vibration while driving | |
Increased front wheel imbalance, tire deformation or uneven tire wear, wheel deformation (hitting the steering wheel) | Balance wheels, deformed or uneven tire wear, deformed wheels - replace |
Severe rear wheel imbalance, tire deformation or uneven wear, wheel deformation (car rear vibration) | Balance wheels, deformed or uneven tire wear, deformed wheels - replace |
Deformation of the cardan shaft / shafts, loss of balancing weights (plates) | Have the driveline repaired by a workshop and then dynamically balanced or replaced |
Large play of the cross in the cardan joint, loss of the retaining ring from the fork of the joint | Check the presence of retaining rings in the grooves of the forks, the axial movement of the cross. Adjust play, replace worn parts |
Loose fastening of parts of the driveline | Tighten threaded connections |
Loose fastening of the intermediate support to the bracket or bracket to the body | Tighten fasteners |
Tires not designed for these operating conditions (on the highway, all-terrain, studded tires, snow chains, etc. are used.) | Use tires according to their purpose |
Uneven wear or peeling of the tread, deformation of the tire, rim | Change wheel |
Car rocking on the road | |
Defective shock absorber | Replace shock absorber (better both at the same time on the same axis) |
Vibration when braking | |
Brake disc warp | Replace disc (better as a couple) |
Increased axial play of the wheel (severe wear on the front wheel bearings or loose hub nut) | Tighten the wheel hub nut, replace the bearing if necessary |
Ovality of the brake drum | Turn or replace the drum |
Stuck piston in rear wheel cylinder | Replace cylinder |
Brake pad has peeled off the base | Replace shoe (better at the same time all on the same axis) |
Weak or broken rear brake pad return spring | Replace spring |
Creaking, squealing when braking | |
Limit wear of brake pads | Replace brake pads (better at the same time all on the same axis) |
Introduction of foreign particles into the lining material (sand) | Usually does not require intervention (can be cleaned with a wire brush) |
Poor quality lining material | Replace shoe (better at the same time all on the same axis) |
Severe brake disc corrosion (due to poor quality disc and/or lining material) | Grind (chisel) or replace disk |
Brake pad has peeled off the base | Replace shoe (better at the same time all on the same axis) |
Weak or broken rear brake pad return spring | Replace spring |
Wheel lock braking | Do not overbrake, use tires suitable for driving conditions |
Increased brake pedal travel (pedal «soft» or «fails») | |
Air in the brake system, leakage of brake fluid through leaks in the hydraulic drive connections, damage to the cuffs in the main brake cylinder, pressure regulator, damage to the brake pipes and hoses | Inspect all lines, their threaded connections and cylinders, eliminate leaks. Restore the normal fluid level in the brake reservoir and bleed the system. If brake hoses are damaged (cracks, swelling or traces of brake fluid) – Replace hoses. If you suspect a defect in the brake master cylinder, replace it with a known good one |
The rubber cuffs of the cylinders are swollen due to the ingress of oil, gasoline, etc. into the brake fluid. | Replace cylinders, hoses, completely drain the brake fluid, flush the system with fresh fluid and pump |
Overheating of the brake mechanisms | Let the brakes cool down. Check the thickness of the pads and brake discs. Use only brake fluid recommended by the manufacturer in the system. Replace brake fluid promptly |
Increased clearance between pads and drum (automatic gap adjustment does not work) | Replace wheel cylinder, bleed system |
Increased (more than 0.25 mm on the edge) brake disc runout | Replace disc |
One of the circuits of the working brake system does not work | Eliminate fluid leakage from the brake system, bleed the system |
Brake pedal travel within normal limits (pedal «tough»), but the car slows down badly | |
Lubrication of brake discs, drums, linings | Clean oily discs and drums, replace pads (in extreme cases, grind on emery). It is strictly forbidden to clean the pads with solvents! Eliminate the cause of oiling (replace the cuff of the axle shaft) |
An ice or salt crust has formed on the surface of the pads (winter); pads got wet | At the beginning of the movement, at low speed, check the brakes. In the rain and after driving through deep puddles, dry the brakes with light pressure on the pedal |
Poor quality lining material | Replace pads (better at the same time all on the same axis) |
Blockage of brake lines: tubes (due to dents) or hoses (due to swelling or delamination of the rubber) | Replace damaged tubes and hoses |
Jamming of the piston in the cylinder, pads in the caliper | Replace the cylinder, clean the contact surfaces of the pads and caliper, lubricate them with SHRUS-4 before installation |
Complete wear of the brake pads (grinding of brakes) | Replace brake pads (better at the same time all on the same axis) |
Brake pad has peeled off the base | Replace shoe (better at the same time all on the same axis) |
Pressure regulator drive misadjusted | Adjust drive |
Defective pressure regulator | Replace Regulator |
Faulty vacuum booster or leaky hose connecting booster to intake manifold | Check the integrity of the hose, its fit on the fittings, tightness of the clamps. To check the amplifier: turn off the engine, press the brake pedal 5-8 times and, keeping the pedal depressed, start the engine. With a working amplifier, after starting the engine, the pedal should be noticeably «leave» forward. Replace defective amplifier |
Incomplete release of all wheels | |
Incorrect position of the adjusting bolt relative to the cover of the vacuum booster | The end of the bolt should protrude 1.25–0.2 mm relative to the end of the cover |
The rubber cuffs of the cylinders are swollen due to the ingress of oil, gasoline, etc. into the brake fluid. | Replace cylinders, hoses, completely drain the brake fluid, flush the system with fresh fluid and pump |
Stuck master cylinder piston (due to corrosion, breakage of return springs, ingress of mechanical impurities into the liquid) | Replace master cylinder, bleed system |
Brake pedal sticking: broken or stretched return spring, severely worn, pedal bushings not lubricated, axle corrosion | Replace the defective spring, bushings, fill them with fresh grease Litol-24, Ciatim-201, -221, Fiol-1U |
Braking of one of the wheels with the brake pedal released | |
Jamming of the piston of the wheel cylinder | Replace cylinder |
The rubber cuffs of the cylinders are swollen due to the ingress of oil, gasoline, etc. into the brake fluid. | Replace cylinders, hoses, completely drain the brake fluid, flush the system with fresh fluid and pump |
Blockage of brake lines: tubes (due to dents) or hoses (due to swelling or delamination of the rubber) | Replace damaged tubes and hoses |
Detachment of the lining of the rear brake pad | Replace shoe (better at the same time all on the same axis) |
Weak or broken rear brake pad return spring | Replace spring |
Deformation of the spacer bar, misalignment of the pads due to deformation of the brake shields | Straighten or replace spacer bar, brake shields |
The parking brake is pulled, the cables are wedged in the shells | Adjust the tension of the cables, lubricate them with engine oil, if the sheath is damaged or the wires of the cable are frayed, and also in case of severe corrosion, replace them |
Poor parking brake | |
Incorrect drive adjustment | Adjust drive |
Drive cables stuck in sheaths | Lubricate the cables with engine oil if the sheath is damaged or the wires of the cable are frayed, as well as in case of severe corrosion - replace them |
Greased brake drums, linings | Clean oily discs and drums, replace pads (in extreme cases, grind on emery). It is strictly forbidden to clean the pads with solvents! Eliminate the cause of oiling (replace axle shaft seal) |
An ice or salt crust has formed on the surface of the pads (winter); pads got wet | At the beginning of the movement, at low speed, check the brakes. In the rain and after driving through deep puddles, dry the brakes by lightly depressing the brake pedal |
Complete wear of the brake pads (grinding of brakes) | Replace brake pads (better at the same time all on the same axis) |
When the parking brake lever is released, the wheels do not brake | |
After a long parking of the car, the pads stuck (or frozen) to the drum | While pulling the parking brake lever or cables, try to carefully (so as not to rip off the brake linings) turn the wheel. Check the ease of movement of the cables in the shells, the pistons in the wheel cylinders, the stiffness of the return springs of the parking brake cables and the shoe return springs. When parking the car, if possible, do not apply the brake, but shift into gear |
Incorrect drive adjustment | Adjust drive |
Drive cables stuck in sheaths | Lubricate the cables with engine oil if the sheath is damaged or the wires of the cable are frayed, as well as in case of severe corrosion - replace them |
Driving the vehicle away from straight ahead (on a flat road) | |
Inconsistent air pressure in tires | Set normal pressure |
Violation of the angles of the longitudinal inclination of the axis of rotation and / or camber of the front wheels | Adjust the angles of inclination of the axis of rotation and / or camber of the front wheels |
Significant difference in tire wear | Replace worn tire |
Irregular settling or broken suspension springs | Replace both springs |
Deformed parts of the suspension and / or car body | Straighten or replace deformed parts and body panels |
Displacement of the rear axle due to broken rods or brackets for their fastening | Replace rods, weld brackets |
Braking of the wheel due to jamming of the piston of the wheel cylinder | Replace cylinder |
Braking of the rear wheel due to weakening or breakage of the return spring of the rear brake pads | Replace spring |
Blockage of brake lines: tubes (due to dents) or hoses (due to swelling or delamination of the rubber) | Replace damaged tubes and hoses |
Jamming of the piston of the wheel cylinder | Replace cylinder |
Blockage of brake lines: tubes (due to dents) or hoses (due to swelling or delamination of the rubber) | Replace damaged tubes and hoses |
Car pulling or skidding when braking | |
Wheel jamming due to delamination of the lining from the base of the brake shoe | Replace shoe (better at the same time all on the same axis) |
Lubrication of brake discs, drums, linings | Clean oily discs and drums, replace pads (in extreme cases, grind on emery). It is strictly forbidden to clean the pads with solvents! Eliminate the cause of oiling (replace axle shaft seal) |
An ice or salt crust has formed on the surface of the pads (winter); pads got wet | At the beginning of the movement, at low speed, check the brakes. In the rain and after driving through deep puddles, dry the brakes by lightly depressing the brake pedal |
Different pressure in the tires of the left and right wheels | Set normal pressure |
Significant difference in tire wear | Replace worn tire |
Brake disc warp | Replace disc (better as a couple) |
Ovality of the brake drum | Turn or replace the drum |
Unequal settlement of front suspension springs | Replace both springs |
Wheel alignment misaligned | Adjust wheel alignment |
Rapid tire tread wear | |
High driving speed, starts with wheel spin, braking «to yuz», cornering with skidding or drifting of wheels | Change your driving style. Adjust tire pressure, wheel alignment more often, check the condition of suspension parts |
Tire pressure out of range | Set normal pressure |
Front wheel alignment misaligned | Adjust wheel alignment |
Increased axial play of the wheel (severe wear of the front wheel bearings or loosening of the hub nut) | Tighten the wheel hub nut, replace the bearing if necessary |
Hit on the tread of materials aggressive towards rubber - bitumen, oil, gasoline, solvents, acids, etc. | Change tire |
Car overload | Do not overload the car |
Uneven tire tread wear | |
Increased wheel imbalance | Balance the wheels |
Tire deformation, rim | Change wheel |
Different tire pressure | Set normal pressure |
Front wheel alignment misaligned | Adjust wheel alignment |
High speed in corners, their passage with skidding or drifting of wheels | Change your driving style. Adjust tire pressure, wheel alignment more often, check the condition of suspension parts |
Increased axial play of the wheel (severe wear of the front wheel bearings or loosening of the hub nut) | Tighten the wheel hub nut, replace the bearing if necessary |
Deterioration of hinges, deformation of suspension or body parts | Replace hinges, straighten or replace deformed suspension parts, spars, body panels |
Play in the steering (see also «Increased steering wheel play») | Replace worn joints, tighten threaded connections, adjust the clearance between the gear and the rack in the steering mechanism |
Increased steering wheel play | |
The gap between the worm and the roller in the steering mechanism is large | Adjust the clearance, if adjustment is not possible, replace the steering gear |
Worn pendulum arm bushings | Replace bushings or swingarm |
Worn tie rod joints | Replace rods |
Steering gear housing and/or swing arm bracket loosened to body side members | Tighten fasteners |
Steering wheel turns hard | |
Incorrectly adjusted clearances in the steering mechanism | Adjust gaps |
Nuts on surfaces, deformation of the worm and / or steering roller | Wash down small damages with a needle file, with significant damage - replace the steering mechanism |
Pendulum arm bushings too tight, lack of lubrication | Adjust the tightening of the nut, lubricate the bushings with Litol-24 and put grease in the cavity between them. To check the tightening torque of the nut, it is necessary to remove the swing arm bracket from the vehicle. The lever must rotate when a load of 1–2 kgf is applied to its end and must not rotate under its own weight |
Low pressure in the tires of the front wheels | Set normal pressure |
Run-out of the car on a flat horizontal section of the road from a speed of 50 km/h less than 500 m (at an air temperature of at least 20°C and after a run of at least 20 km) | |
Braking of one or more wheels | Cm. «Incomplete release of all wheels», «Braking of one of the wheels with the brake pedal released» |
Front wheel alignment misaligned | Adjust wheel alignment |
Low tire pressure | Set normal pressure |
Wrong viscosity oil filled into gearbox | Change the oil to the one recommended in the owner's manual |
Oil leakage from the rear axle | |
Damaged or worn cuffs of the axle shafts or gearbox | Replace cuffs |
Seizures, risks on the surfaces of the shafts on which the cuffs work, shaft runout | Fill minor damage with a file and polish. A new cuff can be a little (up to 1 mm) underpress (placing spacers if necessary), so that its edge works on the unworn part of the shaft. Replace deformed parts |
Increased pressure in the rear axle due to clogged breather | Clean or replace breather |
Traces of shock absorber fluid are visible on the shock absorber | |
shock absorber fluid leak (due to wear of the stem collar, reservoir o-ring, nicks and damage to the stem chrome plating) | Minor «sweating» shock absorber at the top (if there are no leaks) while maintaining its characteristics is not a malfunction. You can check the shock absorbers on a special stand or - roughly - by swinging the car by the wing. No more than 1-2 free vibrations of the car are allowed. If there is significant fluid leakage and/or loss of efficiency, replace the shock absorber |