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PLEASE help.....my brakes

I have a 2000 Audi A4 wagon (Quattro) that have been having problems with the rear brakes since I bought it last October. I have had it to two shops since then, both with the same results. I had to replace all brake components, left and right, two times. The brakes seem to be dragging sporatically and the wheel can be hot to the touch. Pads wear very quickly mainly on the right rear. Only starts after 300-500 mi after work is done. All components have supposedly been checked: parking brake cables and adjustement, brake line blockage, master cylinder function. It is doing it again and this will be the third time since October that it will be in for this same problem. I don’t really know where to go with it. HELP!!!

All components have supposedly been checked

If you could give a complete list of things that have been checked it would be better. If all things really had been checked, then it is unlikely that the problem would persist. A list of “all brake components” replaced would also be good.

You referred to pads so I’ll assume that these are rear disc (as opposed to drum), in which case the first thing I would suspect would be a sticky caliper - either slides or piston or both. Unless those were replaced under “all components.”

See if you can give a complete description of the parts replaced each time and what you have been told was checked.

I also have to wonder why you ended up with two shops and what kind of shops these are. If they are big corporate chains then I’d suggest a reputable (ask around) independent mechanic to check out the brakes.

Any possibility someone accidently put the wrong fluid in the brake system? (like Power steering fluid in the brakes) I know this is a strech.

I agree with cigroller. There is a component failing to perform correctly, but a complete list of parts replaced would help. Other things I can see that may be at fault include the ABS module and the brake bias valve. The brake bias valve controls the amount of pressure going to the rear brakes to keep the brake action balanced.

For some reason the calipers are not releasing the brake pads off the rotors. Perhaps the pads are either the wrong size, poor quality, installed wrong, or the calipers are dirty and/or defective. Any of the these conditions could cause the pads to continue to contact the rotors.

If you don’t want to take the car back to one of the shops you’ve used so far to make it right, then you need to find a shop that specializes in brakes, or Audi’s. As a last, and expensive, resort you might have to go to an Audi dealer.

When the brake job was done, was the fluid flushed to assure clean fluid in your system? Dirty, contaminated brake fluid could be a part of the problem.

i have seen this on other cars, especially in the inside rear pads. The calipers fail to float properly and the pins get corroded and the inside pad doesn’t float and wears prematurely and overheats at the same time. Rebuild the caliper pins and holders and clean them out or better yet replace the pins, use only hi temp brake lube or you can just buy a rebuilt loaded caliper and drip it in.

Well the first go around, I noticed that the right rear rotor was grooved when I went to look at the car before purchasing it. I worked out a deal with the dealer and had a local shop in Morgantown, WV replace both rear rotors and shoes and replaced the right rear caliper that was sticking.

After buying the car, which was at a very good price, and driving for about 200-300 mi I noticed a hot brake smell coming from the right rear wheel. The wheel was hot to the touch also after driving.

I took it back to the first shop and they said that the flexible hose connecting into the caliper was collapsing and not allowing the caliper to release. After that was done it was about another 300 mi and I started noticing the smell and hot wheel again. Always only on the right rear.

I decided to try our local Audi dealer (Clarksburg, WV) reluctantly but could not get into them for about another 500 miles and by that time both rear wheels were getting warm but the right rear was always hotter.

Once I got into the dealer I specifically asked them to check both the e-brake adjustment and cables and condition of the brake lines all the way to the master cylinder. They ended up replacing both rear rotors, pads and calipers. The calipers were suppose to be new, not reman. They also told me that nothing was found damaged with the cable or lines and the adjustment of the e-brake cable was right.

This appeared to do the trick for about 300 miles and two weeks and now it is getting hot again. I just got back from taking it for a driving and checking the rotor temp with a infrared heat gun. The right rear rotor was consistently higher temp than the other three rotors. For instance, on a curvy West Virginia road after about 20 miles the front and left rear rotor were approx 150F and the right rear rotor was approx 205F.

I have also noticed a high-pitched low-volume howl sound coming from the rear once I start moving after a full stop. The sound lasts for about 100-200 feet and then is intermittent and finally stops within approx 500 feet.

Air temp doesnt seem to affect this problem it has happened during below freezing temps and on days like today…60F.

There appears to be no play in the e-brake level also.

I only drive the car about 30 mi/day on both interstate and two lane rural roads.

I have a few other options for repair shops but I don’t know any one else with an older Audi in the area to ask advice on shops. Also it tends to be hard to get it to them due to long distances and getting rides back home.

Thanks for your help and any ideas/suggestions will help tremendously.

PS…I also asked them to check the function of the master cylinder and any kind of bias control…they said that they all appeared to be ok. Don’t know how they checked this.

The fluid was supposed to have been flushed and replaced. At least thats part of what I paid for, the last time it was in was at an Audi dealer. See my reply back to cigroller above for more info. Thanks.

I hope not but I will check. Thanks.

I’ve had a feeling all along that it is probably something more involving a control of some sort. I hope that the dealer actually checked that when asked to. Also I made sure that they knew that this was not the first time it was in for this and that it probably was not in the caliper since it had been replaced once before. See my reply to cigroller above for the list of components replaced. Thanks.