Re: What size tool is needed to remove the brake caliper bolts?
I'm pretty sure the fronts are 9mm, and the rears are 7mm.
I think they did this on purpose because the brake system has to be put into 'service mode', otherwise you risk a caliper piston blowout while the caliper is removed.
By having goofy-sized hardware, it makes it that much more difficult for the average 'joe-schmoe' to mess with his own brakes without at least doing some research about it.
Even in my $30k+ tools at work, I didn't have anything this size.. and I'm too cheap to buy anything right now, so I ground down an old Torx bit and it fit the fronts perfectly. The rears accepted a different size Torx bit that I didn't even have to mess with.