Operation CHARM: Car repair manuals for everyone.

After Repairs Test Drive


Pedal Reserve Checks:





PRIOR TO TEST DRIVING AFTER SERVICING
- Pump the brake pedal to seat the new pads. It normally takes 3-4 full pumps to establish a firm pedal. Ensure you have a firm brake pedal with at least a 75% reserve.

WARNING: Do not attempt to move or test drive the vehicle until a firm pedal is established. The vehicle will have NO BRAKING ABILITY (front or rear) until the brakes are pumped and a firm pedal is established.

- Check for proper brake booster operation.
1. With the engine "OFF", depress and release the brake pedal 4-5 times (this bleeds off the vacuum reserve in the booster).





2. Depress the brake pedal firmly and start the engine.
- If the pedal goes down slightly the brake booster is assisting in brake operation.
- If the pedal does not go down slightly the brake booster is not assisting in brake operation and should be diagnosed for problems.

- Check the tire pressures. Uneven tire pressures may result in a noticeable pull when the brakes are applied.

- Inspect the calipers and all brake hydraulic connections and verify that there are no brake fluid leaks.

- Verify the operation of the rear brakes and emergency brake, adjust if necessary.

- Verify that all lug nuts have been tightened and torqued to specifications.

- Verify wheel bearing adjustment.

- Verify that the master-cylinder is properly filled.

- Perform a series of low speed stops and verify the brakes have sufficient stopping power for a safe test drive.

INITIAL BREAK-IN / SEATING THE PADS
New brake linings must be properly broken in and seated.
- Initially make 8-10 slow and gradual brake applications, slowing from 25 to 10 miles per hour.
- Severe braking or locking up the brakes should be avoided (unless dictated by an emergency situation) for the first 50 miles.

WARNING: Until the new brake linings are properly broken in, overall braking performance will be less than 100%. Braking performance will gradually increase as the new linings are seated.

WHAT TO CHECK FOR WHILE DRIVING
- Verify there are no abnormal noises (metallic scraping, grinding, or clicking). Light brake squeal is common on new pads/linings. The squeal should disappear after the first 20 miles.

- Verify there is no pedal pulsation or steering pull when the brakes are applied.

- Verify that the brake pedal remains solid and does not become soft or spongy after the first few applications.

- Verify the braking performance is adequate to safely stop the vehicle.

POST TEST DRIVE INSPECTION
After the test drive, several components will usually need to be readjusted or fine tuned.
- Check the master-cylinder reservoir and refill as necessary.
- Check the rear brake and emergency brake adjustment. Readjust if necessary.
- Check the wheel bearing adjustment. Readjust if necessary.
- Closely inspect all brake components, and hydraulic connection to verify there are no brake fluid leaks.