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How to service your brakes if you live in an area with snow

Removal of the caliper mount bracket is simple once the caliper is off. It's only held on by two bolts. On my car the fronts are 17mm and the rears are 14mm. The bolts are big, beefy, and rarely seize, although  a hefty pull may be needed to crack the bolt head's rust seal to the hub.

Note: It's best to remove a seriously stuck pin while the bracket is still on the car! Use a pair of Vise-Grips and wiggle/pull until the pin is free. If you leave it until the bracket is in the vise, you may find yourself pulling the vise all over the place!



Now that we've got the bracket off the car, we can assess the problem in better light. The boot on the left was fine. The one on the right was very bad. You can see the rust in the boot groove. We'll have to clean it up really well, and make absolutely certain we've got Sil-Glyde all the way in the bore. This is a rear caliper mount bracket, by the way.)



Now it's a lot easier to get that rat-tail file in there, and to make sure you're filing the inner surface evenly.



It's tedious. File, wipe, file, wipe. But get that bore good and clean! Attention here will be rewarded!
Wrap a piece of old T-shirt around the file, and wipe out the inside of the bore, making sure you're actually getting to the bottom of it. Don't use paper. Paper tears and won't do as good a job as cloth.
Try inserting the pin once in a while. It should drop in with no resistance at all. A bit of side-to-side play is desirable.



Now a very important part: The boot groove. The rear caliper bracket is being shown here, since it's the one with the boot groove that's difficult to clean properly on the car. The fronts are a lot easier because the groove is external and more easily sanded.
See that rust? I'm using my "dentist's pick" to scrape out as much rust as I can.



Then wipe away as much as possible with the old T-shirt wrapped around the pick...



Repeat above as necessary until the groove is as clean as you can get it.
Give the bore one more good wipe to make sure nothing's fallen in.



Clean the boot up and get it ready for installation.
Don't install it just yet, though, we have to grease the bore first. The grease keeps water from touching the surface of the steel, preventing rust.

It's the Sil-Glyde again, and we're using the dentist's pick or other tool to push the grease down the bore to make sure it's completely covered all the way down. We'll end up with too much grease in there, but that's OK for now.



You've cleaned all the rust off the pin's body and head, of course, so we can smear some grease on that, then insert it into the bore.

It's going to be tight, but that's OK. Push with your thumb, wiggling as you go. Eventually the grease will begin squeezing out the top and the pin will descend.



Remove the pin for now.

Now grease the boot up well, and reinstall it in place. The hard part is getting the boot's lip to engage fully in the groove.
Feed it in all the way, making sure it's actually under the groove all around.
Use your finger to feel inside for bulging that would indicate that the boot lip is not fully seated.

Let's give it a bit of a tug. Looks good so far...



Now we can put the pin back, making sure it snaps onto the boot. It will be a bit tight going in.
Give it a pull to make certain the boot has not become dislodged.

Uh-oh! Disaster strikes! Had this gone unnoticed, it would have meant a badly-seized pin in six month's time!



Remove the pin, and CAREFULLY use the dentist's pick to feed the boot into the groove all around. DO NOT poke holes in the rubber!

And as long as the bracket is off, you might as well file off the rust on the pad mounting/slide shim surfaces. Access is a lot better this way.



Now here's a small problem I had this past winter. A combination of rust on the rotor perimeter and slide shims that were deformed with age caused an extremely high-pitched squeak as the shims contacted the rotors. See the shiny areas? Given enough time, that squeak will become a loud, embarrassing "chk-chk-chk" noise that varies with car speed.



Now that the bracket is cleaned off, we can also clean off the slide shim and try-fit it in place (press it down tightly). See the air gap where the yellow arrow is? That's part of the cause of the squeak. Take a pair of pliers and carefully bend the shim tab until it sits flush with the bracket and there's no air gap.



The other cause of the noise was the rust at the edge of the rotor, which expanded the effective diameter until the rust contaced the shims. I just used a file and treated it like an ax or machete, hacking away with a chopping motion at the flaky rust until it was gone. Watch your eyes! Wear goggles! It chips off quite easily. (It's already gone in the left-hand picture. The right one still shows it.)
     


Once you put everything back together, you should expect to see a gap of MORE than 1/16" (2mm) between the shim and the rotor's edge.
Keep in mind you'll have to put the caliper mount bracket back on, and temporarily install the shims and pads dry. Press down on the pads to seat the shims fully, THEN check the gap. If it's anything less than 1/16" (2mm), bend the shims up some more.



It's more convenient to put anti-seize on the caliper mount bracket if it's off the car. (If it's already back on the car because you were checking the shim gap, don't worry about it. Just put the grease on with the bracket in place.)
Update '07: This photo is WRONG. Do not put ANY grease on the mount bracket. See here for more.


That's it. Now you can reinstall the caliper mount bracket to the hub again if it's still off. Torque for the bracket bolts is about 30 lbs.