Opel Frontera UBS. Manual - part 2051

5C – 16 POWER ASSISTED BRAKE SYSTEM

PARALLELSIM

Parallelism is the measurement of the thickness of the
rotor at four or more points around the circumference
of the rotor. All measurements must be made at 22 mm
(0.87 in) from the edge of the rotor.
The rotor thickness must not vary more than 0.010
mm (0.0004 in) from point to point.

Maximum Parallelism Variation

mm (in)

0.010 (0.0004)

REPLACING REAR BRAKE ROTORS

When installing new brake rotors, do not refinish the
surfaces. These parts are at the correct level of surface
finish.

REFINISHING REAR BRAKE ROTORS

Accurate control of the rotor tolerances is necessary
for proper performance of the disc brakes.  Machining
of the rotor should be done only with precision
equipment. All brake rotors have a minimum
thickness dimension cast into them. This dimension is
the minimum wear dimension and not a refinish
dimension. The minimum wear dimension is 16.60
mm (0.654 in). The refinish dimension is 16.97 mm
(0.668 in).
When refinishing rotors, always use sharp cutting
tools or bits. Dull or worn tools leave a poor surface
finish which will affect initial braking performance.

SERVICING THE REAR BRAKE ROTOR

In the manufacturing of the rear brake rotor, all the
tolerances regarding surface finish, parallelism and
lateral runout are held very closely. The maintenance
of these tolerances provide the surface necessary to
assure smooth brake operation.

LATERAL RUNOUT

Lateral runout is the movement of the rotor from side
to side as it rotates on the spindle. This could also be
referred to as “rotor wobble”.
This movement causes the piston to be knocked back
into its bore. This results in additional pedal travel and
a vibration during braking.

CHECKING LATERAL RUNOUT

1. Attach a dial indicator to some portion of the

suspension so that the stem contacts the rotor
face about 22 mm (0.87 in) from the rotor edge.

2. Move the rotor one complete rotation.

•

The lateral runout should not exceed 0.13 mm
(0.005 in).

Maximum Runout

mm (in)

0.13 (0.005)

t

POWER ASSISTED BRAKE SYSTEM  5C – 17

Vibration dampening attachments should always be
used when refinishing braking surfaces. These
attachments eliminate tool chatter and will result in
better surface finish.
After refinishing, replace any rotor does not meet the
minimum thickness of 16.97 mm (0.668 in). Do not use
a brake rotor that will not meet the specification.

Minimum Wear Dimension

mm (in)

16.60 (0.654)

Refinish Dimension

mm (in)

16.97 (0.668)

5C – 18 POWER ASSISTED BRAKE SYSTEM

FIXING TORQUE

Brake Hydraulic Lines

N·m (kg·m/lb·ft)

12(1.2/104 lb•in)

Brake fluid pipe line
Flexible hose

16(1.6/12)

16(1.6/12)

16(1.6/12)

35(3.5/26)

16(1.6/12)

35(3.5/26)

15(1.5/11)

Hydraulic unit
(Vehicle with ABS only)

P&B valve
(If so equipped)

(Mounting bolt)

13(1.3/113 lb•in)

16(1.6/12)

13(1.3/113 lb•in)

P

＆B Valve(If so equipped)

13 (1.3 / 113 lb in) 

13 (1.3 / 113 lb in) 

16 (1.6 / 12) 

12 (1.2 / 104 lb in) 

Vehicle with LSPV

35(3.5/26)

16(1.6/12)

15(1.5/11)

(Mounting bolt)

35(3.5/26)

16(1.6/12)

16(1.6/12)

16(1.6/12)

LSPV

Hydraulic unit
(Vehicle with ABS only)

POWER ASSISTED BRAKE SYSTEM  5C – 19

Brake Pedal

N·m (kg·m/lb·ft)

20(2.0/15)

20(2.0/15)