"Clayton" <clayton320@verizon.net> wrote

It's a cinch.  All you need is the hex wrench (comes in any
metric set - 3mm or so?), some anti-seize, a screw-driver
or clamp to push back the pistons, and a 17mm (IIRC)
socket (works on the lug nuts, too) to release the calipers
so they will swing off the rotors.

Don't forget to replace the wear sensor (it's about $5)
on the side that has it.

FloydR

You've pretty much got the bit already that can be a pain. Only advice I can
give really is to try and undo that rotor to hub bolt (which requires a
hex/allen key type head) before removing the pads and calliper. That way
someone can stand on the brakes to stop the rotor/hub turning while you are
trying to undo it. Which is a whole lot easier than trying to use
screwdrivers etc wedged into the rotor vents. Oh, and buy some new bolts
before hand so you have them already just in case you need drill them out.
Other than that, they are a doddle to do with no special tools required. The
calliper mounting bracket bolts are pretty tight too.

Last bit of advice is don't get BMW rotors, buy some after market brands. I
use the ATE Power discs, they are much harder wearing than the chocolate BMW
ones and cheaper too.

The screw may be a little tight. IME the best way to remove it, is with an
impact driver. Apart from that, about all you need is a spanner to remove
the two bolts securing the caliper mounting bracket, then slide the whole
caliper and mount assy off the disc, or rotor.
BTW, when you fit the new disc, the retaining screw only needs to be done up
lightly. It doesn't need to be really tight. It's only there to stop the
disc moving when changing a wheel etc.
Mike.

Rotors cost in the range of $50 each, and anybody with a sense of mechanics
can install them -- all of them -- in about 2 hours. The dealer, or a
mechanic with the proper assortment of tools can do it in much less time,
but those of us confined to working on the floor of the garage or in the
driveway tend to work a bit slower.

If you can do waterpumps, you can do rotors on a BMW.

It's a metric hex head countersunk setscrew, and yes, they sometimes seize
- although they may also have been damaged earlier by someone using an
imperial hex tool. However, they're easy to drill out as the hex provides
a centre for the drill, and they're fairly soft steel. Once the disc is
off, grind the rest of the head off (if needed), and remove the setscrew
from the back of the hub with Mole grips.

Use some copper grease on the new setscrew, and don't tighten it till it
groans. It's only there to stop the disc falling off when a wheel is
removed. ;-)

Also, make sure the mating surfaces on both disc and hub are perfectly
clean - any grit etc could cause run out.

Buy a set of metric hex heads for a 3/8 drive socket set.