Audi 80/Avant (B4)

since 1991-1995 release

Repair and operation of the car

Audi 80/Avant
+ Technical specification
+ Engines
+ System of production of the fulfilled gases
+ Cooling system
+ Fuel tank and fuel pump
+ Air filter and airintaking channels
+ System of injection
+ Coupling
+ Transmission and transmission
+ Suspension bracket and steering
- Brake system
   Check of brake mechanisms
   Brake fluid
   Check of level of brake fluid
   Check of tightness of brake system
   Replacement of brake fluid
   Disk brake mechanisms
   Measurement of thickness of blocks of the disk mechanism
   Control of a condition of brake disks
   Replacement of blocks of disk brake mechanisms
   Drum brake mechanism
   Measurement of brake shoes of the drum mechanism
   Check of the course of a pedal of a brake
   Disk brake mechanism of back wheels
   Measurement of thickness of blocks of back disk brakes
   Check of a free wheeling of the lever of the parking brake
   Main brake cylinder
   Amplifier of brakes
   Check of the amplifier of brakes
   Regulator of brake forces
   Repair of the hydraulic drive of brakes
   Pumping of brake system
   List of malfunctions
+ Anti-blocking system of brakes
+ Wheels and tires
+ Body electrical system
+ System of ignition
+ Lighting
+ Signalling devices
+ Devices and auxiliary devices
+ Heating and ventilation
+ body Elements
+ Search of malfunctions
+ Specifications

Measurement of thickness of blocks of the disk mechanism

The brake shoes of disk mechanisms having rather big size for forward wheels maintain to 50 000 km. Despite it, you should not forget about regular visual check:


  1. The minimum thickness of blocks has to make 2 mm without the bearing plate. Actually bearing plate – that is a piece of metal on which the slip is pasted – has thickness about 5 mm.
  2. When performing fluent control it is enough to light at the taken-off cap a lamp through an opening in a wheel and to estimate slip thickness.
  3. More exact control is carried out at the removed wheel: to put a ruler to a block and to measure, as shown in the top illustration. Do not forget to examine a frictional slip on inside!

Measurement of thickness of blocks of the brake mechanism of forward wheels:

1 – slip material;
2 – the metal bearing plate.