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

Control of a condition of brake disks

If for check of a condition of blocks wheels are removed, at the same time it is necessary to check also a condition of brake disks.


  1. On disks there should be no deep grooves (which appeared as a result of influence of dirt or strongly worn-out blocks). Otherwise these grooves will deeply crash into new brake shoes that will significantly reduce the term of their service and, besides, will reduce brake influence.
  2. The brake disks damaged by furrows can be processed on the lathe in case they did not become thinner as a result of long service life to the minimum size (watch the table below).
  3. Too thin disks need to be replaced in pairs.
  4. The bluish shade of brake disks does not matter.

Sizes of brake disks

Brake disks
the lobbies which are not ventilated
the lobbies ventilated (the one-piston brake mechanism)
the lobbies ventilated (the two-piston brake mechanism)
the back
Thickness of new disks
13 mm
22 mm
25 mm
10 mm
Minimum thickness
11 mm
20 mm
23 mm
8 mm