I just finished installing 11.75" Wilwoods on the front of my 03 MCS. After confirming torque on all parts and taking out for a test drive to set pads I immediately noticed (heard not felt) a knocking during medium braking. It initially sounded like it was coming form the passanger side, so I took all parts off to confirm torque again. Once put back together and torqued the noise was still present. I'm very confused and slightly perturbed. This is not the first time I've done a bbk swap. The knock almost sounds mid engine. Any suggestions as to what to look at next would be helpful.

During this BBK install I also installed a stud kit and 15mm spacers front and 5mm rear, and DOT 4 brake fluid change.

I'm open to any suggestions....

 

does it knock the first time you brake or every time you hit the brakes. With some brake kits the pads can move slightly in the caliper. So they'll shift one direction in the caliper when you hit the brakes in reverse then the next time you hit the brakes going forward you'll hear them "clunk" back the other direction.

Also, did you torque your wheels down properly? They can make all sorts of noise if they're not torqued properly with studs.

 

A couple thoughts/suggests:
- Did you center the caliper over the rotor with shims?
- Could the caliper be hitting a wheel spoke with a little flex during braking? i.e., is there plenty or clearance between caliper and wheel.
- Could a stud be poking through the hub too far and hitting something?

 

Thanks for all the suggestions. I pulled everything apart and confirmed proper fitment, shims and torque. I put it all back together and still had the same noise. I opted to take her for a test run with the noise present to set the pads. After setting the pads the noise went away, I think the pads had a slight lip on them and were catch the slots on the caliper.

 

Glad you solved the problem. Too bad you had to go through so much troubleshooting and tear-down for what ended up being a simple fix.

 

It was the pads clattering in the carrier when the leading edge hit the slotting on the rotor face (I'm assuming you have slotted rotors). I've seen the same symptoms with Wilwood. I'm glad you had success bedding them.

Also, with Wilwood brakes, be very careful to not warp the rotors in the summer. If you go out for a spirited drive and put some heat in the brakes let them cool before washing your car. The cold water can shock the rotors and warp them.

 

I've personally advocated a slight taper be ground on the pad leading edge.

Part of my Install Tips page.



Another potential source of noise in Wilwood calipers is the tension clips top and bottom of the pad. Over time the flatten out and the pad will be 'lose' in the pad window. While that is ideal for racing, some folks don't like the occasional "clunk" as the pad releases from rotor. While it can be a bit annoying the reality is that it's a good thing- means the pads aren't dragging!

 

i'm running into a similar issue...I need advice from my fellow mini guru's.

After replacing the front pads, with new oem ones I picked up from the dealer near me. I started to notice weird knock when I reverse the car and apply my foot on the brake for first time, after driving forward. If I apply my foot on the brakes again, I don't hear it.
If I drive forward for a while, then try to reverse and apply my brake again, I hear it...I checked all the bolts and everything is torqued to spec.

this been driving me nuts for 2+ weeks now. i appreciate all advice.