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Rear end clunking/thumping after brake job


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Posted

Hi all,

 

2002 silverado 1500, 2wd auto trans, 4.8L with about 150k on it

 

The truck isn't mine, its a friend of mine but he wanted me to put pads & rotors all the way around. He complained that they squealed alot and didn't have good stopping power. So I bought 4 Wagner rotors and two sets of thermoquiet ceramic pads and did the brake job.

 

When I drove it afterward it stops well, but there was some scraping and clunking noises. Figured out the scraping noise was just the backing plates being a little bent/rusted and rubbing the new rotors so that was an easy fix. Now this clunking or thumping noise... apparently it wasn't there before doing the brake job. It ONLY happens when you are coming to a stop, not when taking off from a stop, not while driving, etc. The last 20 feet or so of a stop it makes this rhythmic clunking or thumping noise. I'm pretty sure brakes don't making those kinds of noises.

 

What I know:

4 new pads and rotors installed

he wanted me to swap the front tires for the back so I did that too

he dropped it off to me on his company's tow truck, and when he rolled it off the bed the back wheel climbed the curb

 

I suspected a U-joint but that would make noise when pulling away too. Any ideas??

Posted

Without actually hearing the noise, I would say it"s a warped rotor. Is it cyclical, does pedal pressure make a difference?

Posted

That truck has issues before you touched it. No one brings a truck by for a brake job on with a tow truck unless the truck has major issues already. Being you had to modify a rubbing bracket I be you are working on a Frankentruck.

 

BTW, that truck takes 3 sets of pads.

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