dotframe

I was checking my pad thickness in prep for a PDS event at TWS in a few weeks (anyone else going?) and noticed something a bit odd. I'm still pretty new to DIY on brakes so these may be dumb questions.

After measuring several times I found that 3 of the 4 front pads are about 7.5mm but one of them (the driver's side outside pad) is 6.5mm. Is it normal for one pad to wear so differently than others?

Also, 6.5-7.5mm of material left up front, and 8-8.5mm on the rears is considered about 1/2 that of new pads, isn't it? I don't really want to put on new pads until after my next DE.

Macster

It happens. It may be normal. It may not be normal. Depends. You should always suspect the worst and carefully inspect the brake and brake hardware for any signs of problems other than the usual wear of the pads and rotors. Even if the pad wear is even you should always treat the brakes with the attention safety critical hardware deserves.

Last pad change of my 02 Boxster I found 3 of the 4 front pads worn down to the point the hole for the wear sensor was worn to half its diameter.

The 4th pad, and I do not know its location, was not worn down nearly as much. In fact the wear hole was not breached.

Since the hole diameter is roughly 3/16ths of an inch (0.187") half that is 0.093" and that's a good 2.3mm difference of wear.

Of course, I carefully I inspected the brakes and found nothing amiss. I replaced the pads and rotors and while I can't recall how many miles ago that was it has been over 2 years and maybe 40K miles and the brakes appear to be wearing quite evenly.

One thing you can do is every so often wash the brakes. I use a DIY car wash and spray the brake hardware down -- don't jam the wash wand nozzle right into the area around the pistons/dust boots -- then rinse thoroughly. Be sure to drive the car to dry the brakes to avoid rusting.

What this washing does is it removes the brake dust that builds up/collects on among other things the dust boots. This dust interferes with the slight tendency (intentional) of the brake piston seals to pull/retract the piston and pads away from the rotors. If the pads do not get pulled back they can generate a light squeal. Furthermore, they also can drag and from this run hotter which can lead to increased rates of wear when the brakes are used. The hotter pad will wear more than the cooler pads.

Also, if your brake rotors have holes be sure all the holes are free of any dust buildup to keep brake cooling at an optimum.

Sincerely,

Macster.

dotframe

Thanks Macster. I'll be changing the pads here in the next few weeks and will pay extra attention to the caliper operation, etc. The rotors have 0 cracking in them so far but I think I'll see how accurate of a measurement I can get on the rotor wear to figure out if they warrant replacing.