Brake Rotors- Warranty

[kartking]

I have a feeling that my rotors may need to be replaced due to pulsation felt during braking. Has anyone gotten their rotors replaced under warranty?

[hmp10]

How much mileage?

The R8 rotors have to be replaced with the pads, and it's not a warranty job if deemed part of normal wear. I had to have my front pads and rotors replaced at 17,000 miles (lots of stop & go city driving).

According to my dealer, none of the Audi models have rotors that can be turned. He said they don't even have a brake lathe in their shop.

[mngolfer]

I found the same thing on the rotors for my A8L. They only replace the rotors. One thing I did find is the pad light comes on very early. The sensor light comes on when there is 1/3 of the pad left. I drove my A8L an additional 5,000 miles after the sensor light on my pads came on. I checked weekly to see how much pad was left.

[R84ME]

And man are those rotors expensive! I remember the good old days where rotors for my 325is cost $20!

[hmp10]

Yep. My front-end brake job was around $1200. The dealer thought the rear pads had about 6,000 miles of wear on them at the time the fronts wore out.

[desperado]

One thing I did find is the pad light comes on very early. The sensor light comes on when there is 1/3 of the pad left. I drove my A8L an additional 5,000 miles after the sensor light on my pads came on. I checked weekly to see how much pad was left.

My R8 tech says 6mm (1/4in) is the replacement limit. I've seen 2mm specified on other applications.

However, you should read the thread Pagid Damaged My Rotors? before you decide to use that last little bit of pad material.

[650Berg]

I think you will find that 7mm is the wear limit as specified by Audi. This measurement in inclusive of the backing plate.

[desperado]

Thank you for the correction. I should have looked it up before I posted.

[hmp10]

If the rotors have to be replaced along with the pads anyway, why not use the last bit of available pad? So what if you finally score the rotors, as they're bound for the recycle bin in any case?

[desperado]

I think you will find that 7mm is the wear limit as specified by Audi. This measurement in inclusive of the backing plate.

I did a little investigation and I don't believe that 7mm overall thickness is accurate, either.

I measured the wear sensors on a brand new set of OEM brake pads, as follows:

Front:
Backing Plate 6.7 mm
Wear Sensor 6.0 mm
Total 12.7 mm


Rear:
Backing Plate 6.1 mm
Wear Sensor 5.1 mm
Total 11.2 mm

Note 1: I'm quite confident in the Rear sensor measurement. The Front sensor is constructed differently and is partially hidden inside a hole in the edge of the pad. I guessed at the height of the active surface - it could be higher (thicker), i.e., about 6 mm.

Note 2: In both cases my backing plate measurement includes the plate plus the thickness of the attached anti-squeal pad.

Note 3: I don't have my shop manual here. If someone wants to see if the minimum thickness is specified, that would be great.