Hello,

I'm attempting my first pad/rotor change on my 98 A4 Wagon, and have ran into a problem. The Hex Bolt that holds the caliper holder and secures the rotor- is stripped- possible frozen. Any suggestions?
Thank you Carmen

 

Those bolts are tight. Is it turning at all? If the head is rounded off, it's going to be hard to get off but it can be done. If it's just really hard to get to break loose, use an impact socket and tap it on with a hammer to make sure it's good and seated. The use a breaker bar to get the torque you'll need to get it loose.

 

Bolt came of with w-d, hammer and vice grips. Thank you, btw - Any experience with the caliper piston and getting it to retract? tried c-grips with a lot of leverage and it wouldn't budge. Bled the brakes, nothing. wondering if I need a special tool that twists the piston as it goes in?

 

I'm not familiar with your year but the A4 B7's will require the piston to be rotated, this is for the rear calipers, the fronts can be pushed back in.

 

Yep.. The rear pistons must be twisted back into the fully retracted position. This is because of the threaded portion of parking brake system embedded into the caliper. The fronts should simply press back in. Sometimes they are hard to get to start retracting if they are way out like the pad was starting to get down to the metal backing. You can pick up the retraction tool that fits the rear piston at an automotive store. Make sure when you are twisting the piston that the dust seal is not stuck to the piston or it will twist with the piston and rip open.