NCLA951

I've done the wheel bearings very recently, and I can't wiggle the suspension at all, but I get a thunk from my front right side when I hit the brakes for the first time driving the car. I have recently bled and checked my brakes so I don't think it's the caliper. Once moving I never hear it again, only first thing after sitting. Anyone else had this or have any insight before I go replacing parts? Car has KW V3 coils and shocks. Car drives and brakes straight and gets spirited use regularly.

Thanks!

1987 Guards Red 951

dizzyj

Mine did something similar and it ended up being the steering rack bushings

NoRush993/951

I had a similar issue. The motor mount had failed on the passenger side.
New mounts - drives like new.

NCLA951

I put in Lindsey ultra mounts a few months ago, but I will check their torque, and look at the steering rack bushings. And also see if I can knock it about a bit at the autocross Sunday and narrow it down.

NoRush993/951

Check that all the control arm bolts are secure on the bottom. I had one that stripped out. It was still there, but not holding securely.

jerome951

In addition to the above checks, could be a brake pad moving in the caliper. Try backing up and applying the brakes, then going forward and lightly apply the brakes. If you hear a thunk, it's like the pad moving around.

NCLA951

If it is the pad moving in the caliper does that mean pad replacement or I just messed something up when reinstalling them? I will also check all the suspension bolts.

Thanks!

jerome951

You may have screwed something up but that's hard to do on these calipers. It's possible the pads were stuck to the caliper pistons and now allowed to move around.
Usually it's due to the backing plate being slightly too small. You may have switched pad location and the tolerances between a backing plate and caliper are now just enough to allow for pad movement.

NCLA951

Ok I think it's def the pad moving, when I back and forth I can hear it hit the calipers, but once it's been set in one direction it doesn't reoccur. I took the pads out, cleaned and inspected but they seem fine, and the caliper is good and tight, as well as the rest of the suspension.

Is there a way to correct this (obvs I'll need new high end pads, for safety)?

Tom M'Guinn

Mine do it too. I've tried a couple brands of pads, including Textar from Pelican right now, and still have it. I haven't obsessed on finding a cure, but sure wish someone would.

NCLA951

Before my last autocross I removed the pads, cleaned them off, cleaned up the caliper again and put them back in. The clunk is much reduced if I hear it at all and nothing looked weird in there, so I will continue to drive it hard and see if anything breaks. Thanks for the input all!