| Author | Message | ||
     Glenn Guinto (Glenn) Senior Member Username: Glenn Post Number: 763 Registered: 02-2002 |
I've always wondered what causes the uneven wear of break pads? Is it air in the lines, warped rotor, maybe a combination of both? I changed my front brake pads this weekend LR genuine and everytime I do, I always find that they don't wear evenly. Driver's side has about 35-40% left while passenger's side has about 20% left on the front pad and bear metal on the rear pad to the point that there are holes on the worn pad. My rotors are the DBA cross-drilled and slotted rotors and it's a 99D1 with 78K miles. Please enlighten me on this subject. Thanks! Glenn | ||
| gp (Garrett) Senior Member Username: Garrett Post Number: 2362 Registered: 10-2001 |
poor caliper performance can cause bad wear too. | ||
| Hendrik Behrmann (Hendrik) New Member Username: Hendrik Post Number: 7 Registered: 09-2003 |
it is unlikely that air causes that - you have a long pedal travel etc. You can simply test it: With the engine not running depress the brake pedal a few times. There should be only minimal movement of the pedal and you should feel a hard and sudden resistance. The pedal travel might be 1cm, not much more. A warped rotor would affect both pads ? Perhaps lead to brake squeal or rubbing. Jack up a wheel (gearbox in Neutral, taking care that the car cannot move !!) remove the wheel and turn the hub/rotor (or better let someone else do it so you can concentrate on the rotor). Any relevant warping can be seen. (dial gauge is more sophisticated). I think (Iīm not a professional mechanic) that bad calliper piston certainly cause uneven wear. I had sticking pistons on my rear callipers (one each side) due to rust and dirt. The Range even pulled to one side slightly. And I had the same pad wear. In this case that wear happend because: usually the pistons are pressed out of the calliper housing (and the rubber seal is slightly deformed) by hydraulik pressure and thus presses the brake pad onto the rotor. Once you release the brake pedal hydraulik pressure ceases and the rubber seal goes back into its "resting shape" and pulls the piston a small amount back into the calliper. The brake pad then needs to rub on the rotor no more .. If the piston sticks or has a bad seat (damage to the chrome plating of the piston, rust, dirt) it will not retract from the pad correctly and lead to more wear. If it is that bad that a piston sticks you will notice the rig pulling to one side. Time to overhaul a calliper then. Somehow it is common that the rear brake pads wear faster than the the front pads. But thatīs a different matter and nobody could tell me why that is the case. | ||
| Tony Zuniga (Tony23007) Member Username: Tony23007 Post Number: 197 Registered: 05-2003 |
Like Handrik said you have a bad caliper. Drive the car and on an open road brake hard and see if it pulls to one side, that is direct indication of a bad caliper and one that would need to be replaced. |
