FAQ: Asked by mechanics

Cause: I have fitted new brake pads and the brakes squeal. Why?

Solution: Squeal is caused by vibration of any component under braking. Look beyond the braking system for worn suspension components. Use your Bendix Disc Brake Data Book to check if the right pads have been fitted to the vehicle. Check that the original anti-squeal shims have been fitted to the replacement pads. The calipers may require a complete overhaul.

Cause: My customer complains that his brake pads are wearing out too quickly. What should I do?

Solution: First, check the car's odometer reading to see if the calipers have ever been overhauled. Driver abuse can also cause rapid wear. When the rear brakes are not doing their share of braking, rapid wear of the front brakes will result. Check to see if the booster/master cylinder/proportioning valve are out of adjustment. Calipers must be overhauled at 60,000km intervals. Find out which friction material has been fitted as it may be wrong for the application. Overhaul if necessary.

Cause: After having fitted new pads the customer came back for a check up and we found big differences in pad wear. What's up?

Solution: Uneven pad wear is often a caliper problem, caused by faulty seals, sticking or bent slide pins. Overhaul the calipers on that axle.

Cause: We fitted two sets of pads to two identical cars, but one of the owners is not happy. Why the difference?

Solution: Different vehicle loads, driving styles and road conditions demand different friction material characteristics. A car towing a caravan or tandem trailer may require Bendix Heavy Duty The same car used for normal traffic and driving conditions would be perfectly happy with General CT or Advance. If driven hard, the car may require Ultimate.

Cause: A customer has complained that his pads smoke sometimes and often give off a strong smell. What should I do?

Solution: The pads are simply getting too hot. The most common causes are driver abuse or faulty calipers. Faulty calipers may cause the front or rear brakes to 'hang on', building up heat in the friction material. Get the driver to change his driving habits. Overhaul the braking system.

Cause: What can be done to eliminate steering vibration under braking?

Solution: Disc thickness variation is the cause of this problem. Usually it is caused by the disc being out of alignment when originally fitted. Machine the discs. If they are thinner than the manufacturer's minimum thickness specification, replace the discs.

Cause: We had an owner claim that he ended up in the middle of an intersection after we had machined his rotors. What's the problem?

Solution: Brake pads frequently get blamed for this. The real culprit though is incorrectly finished discs. After machining, always clean off the disc surfaces with 240 grit emery. Then clean up using a non oil based solvent. Repeat the process after fitting. A thorough wipe down will remove graphite and grease.

Cause: We've heard that several different pads fit Commodores. Is this the case?

Solution: Several different pads do fit various models. To fit most Commodores, the pad must have a 6mm minimum thickness backing plate, or a 5mm back plate which has a 1mm raised ear (joggle) on each end.

Cause: How can I find out which pad to fit?

Solution: No matter what make or model of car you are repairing, Bendix is most likely to have the disc brake pad to suit. First check your Bendix Disc Pad Data Book. If the make and model are not listed, call our Brake Advice Centre on 1800 819 666 (8am-5pm Mon to Fri).

Cause: What is Disc thickness variation (DTV)

Solution: Disc thickness variation (DTV) is where the rotor or disc varies in thickness, as indicated in the diagram, around the rotor.