Hello all, I've got a 1999 SC400 with around 120k miles with a front end clunk and harshness when going over bumps, in addition to some metal on metal sounds going on. I've replaced the sway bar bushings and end links with genuine Lexus parts, but the issue remained. I read in this thread that the issue was the floating brake calipers, so I did a test drive and intentionally held the brakes while going over rough pavement and the harshness was still there but the metallic noise was gone. It's got aftermarket wheels and KYB shocks with around 30k miles on them, could this be the source?

Anyway, how should I go about replacing the brake components to alleviate the issue? Thanks!

 

THANK YOU!

I was starting to feel a little hopeless after thoroughly going over my entire car and trying to figure this same exact problem out. I have changed the endlinks, tested the play in the ball joints, bearings, tierods, bushings, etc and I cannot find the problem. I started to think something was just loose in the engine bay but absolutely nothing. I have spent probably 6-8 hours trying to figure this out with 0 luck.

After reading this I took the car out today and went to this same rough patch of road that I ALWAYS hear the problem from (its like a light metal on metal sort-of *tinging* or tapping sound from both sides in the front), and the moment I applied the slightest amount of pressure on the brakes (literally not even enough to slow the car down), NO NOISE AT ALL! I can't believe it.

Does anyone have any input on this? Has anyone else experienced this or found a solution? I am going to take apart my calipers this weekend and see if servicing them might at least help the issue and will report back.

 

https://www.lexussouthatlantaparts.c...&searchString=

I believe this is the correct parts diagram, see the caliper bolts and bushings? I think this is what's needed. Makes sense that it's the calipers, as inputting some brake force will clamp them down enough that they can't rattle over bumps.