FAQ: Asked by mechanics
Brakes are the last thing you want to get wrong on your customer’s car. Not only is it time consuming, it could be a major safety issue! Check out our guide to the most common problem after a service.
Cause: We fitted new brake pads and they squeal. Why?
Solution: Squeal is caused by vibration of any component under braking.
Check the following points:
- Does the rotor face look uneven?
- If the rubbing surface of the pad does not have 100% contact, then noise can occur. Redo bedding in procedures and check.
- Brake hardware, caliper, guide pins, binding, abutment clip damage/ binding, brakes dragging
- Some pads use a grease in between the shim, Bendix Ceramasil Brake Parts Lubricant can be used, for all vehicles, to obtain the best noise performance adding the grease is recommended
Use your Bendix Catalogue App or the online catalogue to check if the right pads have been fitted to the vehicle. Ensure the anti-squeal shims supplied are fitted correctly with the Bendix brake pads. Check if you have used the correct lubricant, such as Bendix Ceramasil Brake Parts Lubricant on the right components. The calipers may require a complete overhaul if the car has high mileage.
Problem: Rapid pad wear.
Cause: My customer complains that his brake pads are wearing out too quickly.
Solution: High pad wear can occur for a number of reasons, firstly the hardware of the car needs to be in good working order. Caliper seizures or uneven braking causes high wear rate. First, check the car's mileage and service history to see if the calipers has ever been overhauled. 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.
The issue may also be related to the pad selection, heat cycle and driving style. Driver abuse can also cause rapid wear. When brake pads continue to operate at above rated temperatures the wear rate increases dramatically. Find out what brake pads has been fitted as it may be wrong for your customer’s driving style application. If the vehicle is heavily loaded or the driver drives in a spirited manner, then review the pad selection from the Bendix Brake Pad Selection Guide, or go to the Brake Selection Guide and choose the appropriate material for your customers driving style/ load conditions, and change brake pads if needed.
Problem: Uneven pad wear.
Cause: After fitting new brake pads, customer came back for a check up and we found huge uneven pad wear.
Solution: Uneven pad wear is often a caliper problem, caused by faulty seals, sticking or bent slide pins. Overhaul the calipers on that axle. Ensure you have used the correct lubricant, such as Bendix Ceramasil Brake Parts Lubricant on the right components
Problem: Right material for the job.
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.
Problem: Smoke and odour.
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.
Problem: Steering vibration under light braking.
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.
Problem: Poor braking performance after disc machining.
Cause: A customer complained about low stopping power after we machined the brake 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.
Problem: Which pad fits in the caliper?
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).
Problem: What is DTV?
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.
Problem: Which pad for Commodores.
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.