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Horrible noise problems after brake job

Hi

Car data:

89 park avenue 190,000 miles

Just replaced front pads and rotors. I put Wagner thermo-quiet pads on (all ceramic), and decent, beefy rotors (not made in the far east)

I had problems taking off the tires on both wheels. Some grease monkey had put em on with an impact wrench, and didn't stop tightening till the bolts blew powder, I'm sure. (AND, which probably warped the existing rotors, and caused the braking vibration I was trying to fix). I had to heat 3 bolts on both sides.

Callipers looked good on install, sliders moved freely, etc.

On initial test drive, I had a bad scraping noise from the front left. I stopped, pulled off the tire again, inspected, nothing was visibly rubbing (except the pads to the rotors, of course). Put everything back on, drove away. The scraping noise stopped after 4 or 5 medium brakes from 50 to 30 mph.

Driving down the highway, I get this LOUD whining noise (About the pitch of a fire alarm). Doesn't happen all the time, if I rip the steering wheel and "slalom" the car, it'll go away usually, or if I hit the brakes hard.

The sound is NOT speed dependant (IE, is does not change pitch with speed). It does get a little louder with speed, but the pitch remains constant from

5mph up to 65.

I can't feel any drag on the car, still coasts fine, steering is centered, vehicle tracks fine, no pedal or steering wheel vibrations, just this intermittent noise.. It's embarrassing, quite frankly

Any help would be appreciated.

Reply to
Me
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Maybe the calipers are not letting the pads retract when you take your foot off the brake.

Lots of possible causes, and very hard to diagnose on usenet!

John

Reply to
John Horner

Calipers that 'look good' doesn't mean they are working properly. More than likely the piston(s) are sticking in their bore. While you had the opportunity, you should have tested them and probably serviced/replaced them....being that far into a brake job and not servicing the calipers doesn't make much sense. How many miles are on the calipers?

Have you raised the front end and tried spinning the tires? Doing this would go far in helping you diagnose the problem. Did you use a pad lubricant on the backing plate of the new pad? If/when you service the calipers, be sure you use the lubricant on the sliders and the backing plate of the new pads. I'm not familiar with ceramic pads, maybe they are inherently noisy for sometime until they get broken in, but I don't know. The best guess is the calipers need attention.

Hope this helps some.......

Dave S(Texas)

Reply to
putt

I don't know if it's possible on your vehicle, but I had these exact same symptoms on my motorcycle after a brake job several years ago. What it turned out to be was the pads were installed backwards with the backing plate facing the rotor instead of the pad material. Just a careless accident that was easily fixed.

Cheers - Jonathan

Reply to
Jonathan Race

I hope you're saying impossible on the original poster's vehicle, because it is not impossible on my bike.

Cheers - Jonathan

Reply to
Jonathan Race

Reply to
sidewinder

I have a '95 Harley-Davidson Softail Custom, and the brake pads are symmetrical on both sides and both ends. It was sheer carelessness, but it is very possible to reverse a brake pad if you're not paying attention to what you are doing. I don't know anything about the original poster's brakes on his car, I was just suggesting that this has happened to me with similar results and maybe he should check it out as a possibility.

Cheers - Jonathan

Reply to
Jonathan Race

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