wtb-z

Car: Stock C5 brakes, 100-200TW tires.

I am on my second set of Wilwood H front pads, which I have been pretty happy with so far.

Recently, however, I noticed something that seemed off regarding the brakes.

While the car is parked with a front wheel in the air, it is pretty hard to turn the hub/rotor/wheel assembly. It will turn, but there is enough drag to make it pretty hard to do by hand.
The pads seem to be grabbing the rotor, even with no brake pressure. Compress the caliper a bit (as if changing pads) and the assembly will start to turn easily.

Is this normal behaviour? I haven't noticed any other issues, but other race pads I have used before (Hawk DTC, mostly, and Project Mu) have not done this. With a wheel in the air the hub/rotor/wheel assembly would always spin pretty easily, cold or warm.

Thoughts?

69427

I have a somewhat similar experience with the H compound. I just chalked it up to the rotor's rough surface from running this compound, and the lack of retractable lip seals in my (Wilwood) calipers.

I'm open to correction if I'm wrong in my assumptions here.

Bill Dearborn

Been using Wilwood H pads for 10 years and never really noticed the phenomena you are describing. However, I probably wasn't really paying attention.

Bill

flash911

From a general perspective - While it's common to see some brake pad 'drag' on a rotor, I've never seen it lock up to the point of not turning. I have seen master issues that caused the fronts to lock up.

The tow home was fun.

555ss

the thing to try is open the bleed and see if it is held with some pressure or not. do the calpier pistons push back easily or not the pad cannot "grab" with out some pressure on the pistons so it is either a hyd issue or tight pistons in the bore. I have used H pads for 5 years bent calipers and uprights but never had one drag with out the brake being applied...
Now my AP's on the other hand have anti knock back springs and they do have some drag.

wtb-z

Thanks for the feedback, all. Interesting split in experiences.

My calipers have a lot of events on them at this point but I have not noticed difficulty in pushing the pistons back in. Last time I checked I still have intact dust boost on the pistons, although they are looking increasingly worse for wear.

I am pretty sure this rotor grabbiness did not happen with my street pads (HP+) in the caliper either, although I will sanity check.

SouthernSon

May be time to rebuild the calipers with new O rings in the cylinder. They do require replacing even when not leaking. They can cause what you are describing.