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Burning rubber smell

My '03 Audi A4 sometimes smells strongly of burning rubber when I use the brakes. Not always, and I keep looking for the different circumstances for rubber smell/no smell, but still can’t figure it out. I replaced front brake pads/rotors for unrelated reason and the smell still occurs. Two mechanics couldn’t explain it but were not alarmed. I say something must be happening!

What was the unrelated reason? It may be more related than you think.

The smell you describe more often than not comes from a dragging pad, caused by sticky/stuck caliper sides. Have you checked your rear brakes too?

You’re right, front brake wear might be related, and all I know about my rear brakes is that they’re not worn down.

I was told that brake pads are not made of rubber, so it’s not the brake pad. And the smell comes only when I’m actually braking. But your comment about calipers made me wonder: could bad calipers mean the brakes are touching the rubber tire? And if so, where on the tire should I check for wear?
(I suspect my new questions explain the name “bus rider.”)

Brake pads are not made of rubber, but the smell they produce when dragging often comes across as a burning rubber smell.

Describe the condition of all of your front brake parts when they were done. Were all four pads worn evenly? Was there any odd discoloration or smell? What did the rotors look like - any signs of excessive heat on them? How does the brake fluid look? Is it really dark and stinky? Did you completely clean up the caliper & lubricate the slides and such?

I really think you need to get it sorted out sooner rather than later b/c if you have a problem with brakes overheating, the results could be really bad (like death or something).

Agreed.

are these wheels standard or did you put on some different rims and tires that might not have proper offset and clearance. Hot brakes, like clutches, have an amine or fish like odor when overheated. I wouldn’t think the pads are the odor, as they don’t smell like rubber. You may want to look at the rubberized parts on the calipers, pin dust covers, your cooling bracket on the brake may be bent and not providing the air flow you need as you brake

One thing to check is to make sure nothing is leaking onto the brakes, front and rear, any fluid usage anywhere?

I bought this car used–a few months ago–and now I realize I’d better take it to the mechanic and ask him the questions suggested here. Thanks to all for the input, which is letting me know a lot more about what might be going on and what should be be looked at.

A small oil leak, say from a valve cover gasket that burns off on the exhaust manifold can smell just like burning rubber, so I would check for a engine oil leak in addition to checking the brakes.