OK, I'm installing my A8 BBK tomorrow after work and I want to be sure I'm prepared with all the tools before I start taking stuff apart. What type of bolts hold on the calipers to the carriers, and the carriers to the hubs? I think (Hiwords, correct me if I'm wrong) that the calipers are held onto the carriers with allen head bolts, and I have allen wrenches and I believe I have something I can use as a cheater bar over them. How about the carriers to the hubs? Are those also allen head bolts, or are they regular hex bolts, or god forbid, torx? Anyone know? I don't want to tear this thing apart and then find out I don't have the right tools. TIA for any info.

 

Its a 7mm allan bolt that holds on the caliper, its either a 21mm or 22mm hex head bolt that holds on the caliper assembly to the hub. (VERY TIGHT)

 

Are you sure it isnt 17mm? Im not 100%, but i dont think its that big. It was a awhile ago since i did brakes on either car.

 

Of course im sure. A 17mm allan is the bolt that holds the CV axle to the hub behind the wheel's center cap. The brake caliper bolts are tiny.

 

Think he means 17mm vs 22mm for the carrier bolts. No problem in any event - I have all of those tools, plus PB Blaster, brake cleaner, and a handy and comprehensive list of curse words to help get them off. Thanks guys - saves me a potential trip to the store

 

I was talking about the carrier to the hub. Like i said, it was a long time ago. I just thought it was smaller than 21mm

 

I know that on my Z, there were 17mm bolts to hold the calipers to the hubs, and that seems like it's been beefy enough on most cars I've worked on, but being an Audi with it's typical overbuilding, I could believe it if it's 21 or 22mm too. I have them all anyhow, so no sweat. Thanks guys.

 

Maybe you should read the DIY I wrote on this very subject.

 

Is it on this site or audizine/audiworld? I have one from one of those sites but it doesn't mention the bolt styles/sizes.

 

The DIY section has what your looking for. And yes, i was right, the bolts on the back are 17mm and not 21/22mm.