Hey guys, just did the front brakes on my a6, which were pretty easy, but having a hell of a time with the rears. I got the rear calipers off and replace the rotor and pads, but i cant get the piston to compress at all to fit over the new pads. I took the cap off of the brake reservoir and when i use the piston compression tool i dont even see the brake fluid bubble..any suggestions?

BTW i have an 2005 3.2 A6 Quattro. Thanks

 

thats an easy on,you need a special rear brake caliper tool,it cost about 60 bucks,it pushes and turns at the same time.i had the same problem when i was doing my rear brakes,thought i was going crazy

 

I use a large set of pliers and, carefully, grap the caliper puck, rotating it while pushing in with my fingers. A helping hand is beneficial.

Bob

 

Hrm, I had the piston resetting tool that I rented from autozone, but it was defiantly not twisting the piston at all, was just pushing. Any idea where i can pick up the right tool?

Thanks guys.

 

My local dealer told me they needed to do the rear brakes because of some process they do ... I wonder if this is what he was referring to?

This is what I was told:
"rear brakes on A6’S and A8’s have to be done by Audi, as the rear calipers have to re-tracked with the VAG-com tool."

 

Fluid That's bull crap!

Bob Martin said it right. The pistons have to be turned as they are pressed in. It is a simple step once you know how. A little pressure with a twist does the job. If you want to get fancy you can purchase a tool on EBAy such as item # 160266787941 for $59.95. I think I paid a bit less for mine a few years ago.

 

"Calipers have to be retracked with the VAG-COM tool". That's a new one! They probably will need to adjust your muffler bearings and flush your fuel system at the same time. Otherwise, you might not make it home!!!!

Bob

 

Thanks, I'm going to give it another try this weekend so will let you guys know how it went.

 

This isn't like the older Audi's (pre 05). You need to use a software tool (VAG101) because of the electronic parking brake. There are some on Ebay for $95. You can view the manual at http://www.auteltech.com/pdf/MaxiEST..._Manual_EN.pdf.

 

Actually thats not bull crap. The rear calipers on both the A6 and A8 have an electronic parking brake which is controlled by a module thats a slave to the ABS control unit. In other words the piston will electrically move inwards and outwards using the VAG COM or VAS 5051/5052 scan tools. Manually twisting it in can break the motor.
The A6 is much easier to do the rear brakes because it only requires hitting a few buttons, the A8 is retarted, you have to retract the piston with the scan tool, then measure the pads you took off and record them in mm. Then you input the new pad thickness into the scan tool so it knows how much to spin the piston back so you won't drag the brakes. If anyone wants to know more about this technology just ask me. I've done hundreds of brake jobs on both.