Chevrolet Sonic Repair Manual: Brake Rotor Thickness Variation Measurement
Warning:
Refer to Brake Dust Warning.
Note:
Any disc brake rotor that exhibits thickness variation exceeding the maximum acceptable level must be refinished or replaced. Thickness variation exceeding the maximum acceptable level can cause brake pulsation.
- If the inboard friction surface of the brake rotor is not accessible, reposition and support the caliper with the brake pads. Refer to Front Disc Brake Pads Replacement.
- Clean the friction surfaces of the brake rotor with denatured alcohol, or an equivalent approved brake cleaner.
- Using a micrometer (1) calibrated in thousandths-of-a-millimeter, or ten-thousandths-of-an-inch,
measure and record the thickness of the brake rotor at 4 or more points, evenly
spaced around the brake rotor.
Make sure that the measurements are only taken within the friction surfaces and that the micrometer is positioned the same distance from the outer edge of the brake rotor, about 13 mm (1/2 in), for each measurement.
- Calculate the difference between the highest and lowest thickness measurements recorded to obtain the amount of thickness variation.
- Compare the thickness variation measurement to the following specification:
Specification
- J93, J94: 0.02 mm (0.0008 in)
- JPW, J97: 0.02 mm (0.0008 in)
- J93, J94: 0.02 mm (0.0008 in)
- If the brake rotor thickness variation measurement exceeds the specification, the brake rotor requires refinishing or replacement.
Note:
Whenever a brake rotor is refinished or replaced, the assembled lateral runout (LRO) of the brake rotor must be measured to make sure optimum performance of the disc brakes.
Brake Rotor Thickness Measurement
Warning: Refer to Brake Dust Warning.
If the inboard friction surface of the brake rotor is not accessible, reposition
and support the caliper with the brake pads. Refer to Front Disc Bra ...
Brake Rotor/Drum Balance Inspection
Support the vehicle drive axle on a suitable hoist. Refer to Lifting and
Jacking the Vehicle.
Remove the tire and wheel assemblies from the drive axle. Refer to Tire
and Wheel Removal and ...
Other materials:
Immobilizer Operation
This vehicle has a passive theft-deterrent system.
The system does not have to be manually armed or disarmed.
The vehicle is automatically immobilized when the key is removed from the ignition.
The system is automatically disarmed when the vehicle is started with the correct
key. The key uses a ...
Special Tools
Illustration
Tool Number / Description
CH?E9376
Holding Wrench
CH?E9400
J-45859
Hub Spindle Remover
DT-6332
Seal Protector
DT- ...
Engine Replacement (Manual Transmission)
Special Tools
J-45859 Wheel Drive Shaft Remover .
CH-807 Closure Plugs .
For equivalent regional tools, refer to Special Tools.
Removal Procedure
Remove the battery and battery tray. Refer to Battery Tray Replacement.
Relieve the fuel system pressure. Refer to Fu ...
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