Paulsome

Hi all - I'm looking for info on what kind/size bolts these are. In order to replace the rotors on my '05 1.8, it looks like at least one of the two brake caliper bracket bolts needs to be removed so that the bracket can swing away far enough to get the rotor off. I've seen different references for what to use to remove them - for the rears some say you need a T50 Torx bit, others that you need a 8mm Hex bit, and yet another that they are something called a triple square/12 point bit (no size was given though).

So I'm wondering if anyone here has a definitive answer on what they actually are? I also need to replace the front rotors, so would also be looking for the correct bit to remove those as well.

For the rears, the Torx bit seemed too loose, so I didn't try it. The hex bit was tight enough to give it a shot, but it didn't budge, and I got wary about stripping it out. Didn't try the triple bit because I don't own any or know anyone who does. Looking for confirmation of whether I actually need them before having to buy them. Thanks.

rreyes

More than likely it's a triple-square bolt there; every VW and Audi I've had to change the rear brakes on had them. Your best bet is to get an inspection mirror and look at the fastener, that will tell you definitively what you'll need. Also, you can pick up a decent set of triple-squares on Amazon :

turbo510

Do you mean the caliper slide pins? Those do require an 8mm hex drive I believe. But to remove the rotors, the "frame" which supports the caliper must be move out of the way; I suspect that is what you referred to. On my '05, that is attached to the Aluminum upright by two bolts, with 21mm hex heads, I believe. I had mine removed last month to replace the disks with cross-drilled Zimmermann units, and painted the caliper and frame with engine enamel.

Paulsome

Yeah, the caliper support bracket/frame/carrier (I've seen various terms used for it) is what I was referring to. The rear calipers themselves came off easily enough by removing the slide pin bolts with a 13mm wrench, but that only got me access to replace the pads. I was finally able to get the top support bracket bolt off using an Irwin bolt extractor socket. With the top bolt out, I was then able to pivot the bracket enough and remove the rotor without having to mess with the bottom support bracket bolt at all.

As rreyes suggested, I did end up buying a triple square bit set, but unfortunately none of the sizes in the kit fit nicely. Looking at the bolt head after removal, it does look like the 8mm hex bit might have been the right one, but they were just too corroded to get it to fit well enough. Either way, I replaced the bolts on both sides with a traditional hex head Class 10.9 M10 x 1.25 x 50mm bolt to make life much easier next time around. New drilled and slotted rotors are in, and seem to be performing well!

turbo510

If that bottom bolt was properly tightened, it would be difficult to rotate the frame I'd think. Might be a good idea to remove that bolt at some point and install a new one, and securely tightened. By the way, I've got to give you guys on the N.E. coast credit for dealing with corrosion. SoCal has its problems, but corrosion is usually not one of them.

Paulsome

Totally agree, and my original intent was to replace both the top and bottom bolts. Unfortunately, access to the bottom bolt was cramped enough that I couldn't get the bolt extractor socket on securely enough to attempt removal, and it gave me the same issues as the top one with the 8mm bit. What gives me comfort is that the frame bracket did not move easily at all - it took a ton of effort to move it just barely enough to get the rotor off and then back into place, but I'll definitely keep an eye on it.

Yeah, the rust struggle is real. It's generally why we can't have nice things haha. I'm envious of all of you on the West Coast and other salt-free areas of the country. Half the bolts on everything I own look like they've been sitting on the deck of the Titanic for the last century. PB Blaster, propane torches and breaker bars end up being my go-to items more often than not.

aware

Searching for info on rear caliper bracket bolts. Mine are 18MM

Do the BOLTS need to be replaced?

I found an exploded parts diagram on my PC, that says replace. Is that needed?

I always use thread lock.

I am replacing the rear rotors on a 2011 Q5

There is nothing said at https://www.audiworld.com/how-tos/a/...alipers-422143

THANKS IN ADVANCE!

lyleswk

I've done at least 20 brake jobs on various cars and never replaced the bracket bolts except the one time I had to cut them off because they were rusted in place. Just make sure you torque them to the proper torque.

Paulsome

Agreed, as long as the threads and heads on the existing bolts are in good shape, replacement shouldn't be necessary. I replaced a couple on my rear calipers just because there was no way I was going to be able to tighten them back down to the torque spec with how corroded the heads were. If you do decide to replace them, make sure to use higher strength bolts (i.e. Grade 8 for standard or Class 10.9 for metric). Anything less is not worth the safety risk in my opinion.

Alberti

where did get your brakes and calibers?