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jriddle11
04-04-2007, 08:23 AM
Hey Everyone I would like some assistance.

I have a 03 A4 Sport with 67K miles on it I bought the car used from an Audi dealership with 50K on it. Over the past 10-12K I have noticed that under braking I feel the car vibrate a bit. It is not terrible, but it is noticeable and annoying. The car is Audi Certified so I will take it to dealership first to see what they say. I am stealerships best customer, because I don't now crap about cars parts. I just love cars and always want them running well.

At first I thought it was because my tires may be out of round, because with my old wheels I had some road noise. So I had new wheels and tires put on last week. The road noise is gone, but the vibrations under braking are still there. I have a friend that does some work on cars (he does not know Audi's) and he looked at my pads and rotors and said they both look great and have plenty of meat on them.

I am just trying to protect myself and have an idea of what it maybe before I go to the dealership to have them inspect the car.[wrench]

junkie1.8TQ
04-05-2007, 02:48 PM
Your rotors are warped...

VroomVroom
04-05-2007, 03:37 PM
Yep. If you only have vibration when braking, it's the brakes. The most common diagnosis is a warped rotor. Do you feel the vibration in the steering wheel? That generally points to a warped front rotor.

Spongebob05
04-05-2007, 03:40 PM
Yep. If you only have vibration when braking, it's the brakes. The most common diagnosis is a warped rotor. Do you feel the vibration in the steering wheel? That generally points to a warped front rotor.

x2

quattshot
04-06-2007, 08:11 AM
Get em trued at your local PepBoys or buy a new pair.

jriddle11
04-10-2007, 10:36 AM
I feel it in the steering wheel and the floor. I take it this is something that you can not tell by looking, correct? Because my rotors and pads look good.

va-terps4
04-10-2007, 11:27 AM
Rotor warping can be caused in a number of ways. If you torque your lug bolts unevenly, that'll do it for sure. If you get 'em really hot and then sit still with the brakes applied that can do it. It could also be a result of age - the rotors eventually lose enough material that they can't handle the heat of normal use.

You'll need to have your rotor thickness measured to see if they can be turned safely. If they get too thin, they aren't allowed to be turned by law. Even if they can be turned, the warping might come back because you will be removing metal from them - meaning they are that much more susceptible to warping.

If these are the original rotors, I would say you should plan on getting new ones.

EBG 18T
04-10-2007, 05:39 PM
it could even be as simple as pad deposits on the rotors.

jriddle11
04-10-2007, 07:15 PM
Rotor warping can be caused in a number of ways. If you torque your lug bolts unevenly, that'll do it for sure. If you get 'em really hot and then sit still with the brakes applied that can do it. It could also be a result of age - the rotors eventually lose enough material that they can't handle the heat of normal use.

You'll need to have your rotor thickness measured to see if they can be turned safely. If they get too thin, they aren't allowed to be turned by law. Even if they can be turned, the warping might come back because you will be removing metal from them - meaning they are that much more susceptible to warping.

If these are the original rotors, I would say you should plan on getting new ones.
Where can I get them measured? Pep Boys, Advance Auto, Dealership?

I don't know if they are the original rotors or not.

va-terps4
04-10-2007, 07:30 PM
Any place that turns rotors can measure them. If you don't want to get fleeced at the dealership, Midas comes to mind. If you end up needing rotors, I would look at some of the aftermarket options. You don't have to go with a bigger size to upgrade...

jriddle11
04-11-2007, 08:56 AM
Are there any rotors any of you would recommend or that I should stay away from?

va-terps4
04-11-2007, 09:14 AM
I've never done a brake kit on my Audi cars, so I don't have personal experience with any of them. But people seem to like Stoptech and Brembo stuff across the boards.

jriddle11
04-11-2007, 10:04 AM
Ok, thanks

RAudi Driver
04-13-2007, 03:32 PM
Get yourself a set of those cyrogenically treated rotors. These things never warp. I have a set on the Maxima and they are great.

nudavinci64
04-20-2007, 02:36 PM
yes def rotors.. I have 42xxx on my car and I am on my third set on the front and 2nd set on the rear which need new one NOW. Audi's pound Rotors to death. I don't know what it is, but I have never had this issue with rotors. If you are going to just have someone do the work for you. It will be almost worth it to just buy new rotors. I ended up going with some cross drilled/slotted to help elevate the heat. I did not have the money for the 2 piece floating BBK rotors which people have. If you can afford it go with those. Your warping days will almost dissapear

jeremy@matrix
05-02-2007, 01:51 PM
it could even be as simple as pad deposits on the rotors.

Yes.

Go with an aftermarket rotor (preferrably an OEM drilled like the Zimmerman's) and an aftermarket pad set like the Pagid RS4-2-1.

We haven't seen "warped" rotors on the A4's very much but the cars with HP2 fronts (B5 S4, A6/AR 2.7T/V8) are notorious for "warped" rotor sensation. The conclusion is that the rotor metallurgy isn't porous enough to allow the fresh pad material to be accepted into the rotor. When the pad material isn't accepted/bedded into the rotor very well, the pads will typically leave deposits on the rotor, which can lead to a “warpage” sensation (the rotor most likely isn’t actually warping however).