This guide is dedicated to helping you repair your own drum brakes without losing your temper or forgeting what goes where. Drum brakes are sometimes refered to as a nasty job, especially if the wheel cylinders have failed and the brake fluid has turned all the brake dust to sludge! It doesn't have to be that bad.

1 The first thing you must do is remove the drums from the car and check them for wear. Make sure you don't damage the backing plate by trying to pry off a stubborn drum. Most of the time a quick rap with a small sledge hammer will dislodge a rusted drum, but make sure the shoes are not locking the drum in place. As the drum wears a rust lip will form on the back edge that will grab onto the shoes when you try to remove it unless you back off the adjuster screw through one of the little access holes in the backing plate. If you are replacing the whole assembly chances are the whole thing is really rusted and corroded together, so you will probably not be able to back off the adjuster, leaving you with the nasty job of prying the drum off. Just don't damage or bend the backing plate in the process and you will be OK.

 2 Once the drums are off you can check them for wear and measure them to make sure you are getting the right drums to replace them with. There are lots of ways the drums can wear without you being able to see it with you eyes alone, but that is a whole topic in itself we will get to later. lets assume you are just going to replace the entire assembly and get back that new car stopping ability once again.

3 The first rule of drum brake repair is (DO ONE SIDE AT A TIME). If you tear down both sides before you start putting things back together you will not be able to look at a completed side to know where the springs and shoes go, leaving you helpless and confused. I have done brake work professionally for over 15 years and still do it this way, there are to many different spring configurations to be able to remember them all!

4 You will want to strip everything down to the backing plate (the backing plate is the plate the shoes and wheel cylinders are mounted to). You can pick a can or 2 of spray brake cleaner from a parts store to remove the dust and sludge from the backing plate.

5 Check the backing plate for wear and make sure it is not bent, especially if you were using a prybar to remove a rusted on drum! The backing plate is the foundation on which you will make or brake a good brake job, if you feel the spots where the shoes ride against it you can see if the wear is bad enough to warrant a replacement of the backing plate or just a little TLC. I usually try to save the plate at all cost because there is not ever a replacement on hand except at a dealership (special order most of the time). If there is rust build-up on the plate where the shoes make contact clean it all off with a file or wire brush attachment on a die grinder. Get the plate clean and dry and then apply some brake caliper grease to the areas that the shoe will contact, this will assure a smooth, squeak free stop after you are finished.

6 Now that the backing plate is ready to go, mount the new wheel cylinder to the plate and bleed the air out of your brake line. You don't want to go through this whole job and have a wheel cylinder blow on you in a month or 2, causing a complete repeat of the job and new shoes again. If the drums are shot so is the wheel cylinder, you can count on it. The wheel cylinders and the whole brake system for that matter, get moisture build up over time from the fact that as brake fluid heats up and cools down every time you drive, moisture develops. This makes rust pits in your cylinder bore that tears apart your little plunger seals inside the wheel cylider. As the fluid starts to escape from the seal it will build up in the dust seal on the outer end of the cylinder, just waiting to spew over your brake shoes at the right moment. I have also witnessed the complete freeze up of cylinders that rusted to the point of complete siezure, leaving the unsuspecting driver with no rear brakes at all. Enough about that, lets get it put back together.

7 With the wheel cylinder in place and properly bled (or bleed them last when everything is put together , it doesn't matter.), you can look at the shoes and determine if you have a primary/secondary shoe setup or not. Again this is where you will want to look at the other side and determine the shoe design, some cars use a primary shoe that is somewhat thinner or smaller in friction material than the secondary or trailing shoe. the primany would be the one closest to the front of the car. Put the correct font shoe on and re-attach the hold down springs. Get the other shoe on and do likewise, then install the adjuster hardware if applicable. last hting is to put the tension springs on that hold the shoes together, this is where you may need a brake tool made for the job so you don't put a screwdriver through your eyeball trying to stretch a spring. They make some pretty inexspensive brake tools that work on most cars so get the tools you need.

8 Once you have the shoe/adjuster assembly mounted and all sprung, slide it back and forth on the backing plate to make sure it is not binding on anything. Also look at the anchor bolt at the top of the plate (on most cars) and make sure the shoes are contacting it or resting on it in the concave portion of the shoe plate. A rusted or stuck emergency brake cable can cause the shoe to pull out of place and it will not rest on the anchor bolt or float free when you try to slide the shoes back and forth. Make sure youe E brake cables are in good condition and this won't be a problem.

9 All you have left to do is get the shoes adjusted to the new drums properly. Don't assume the adjuster should be close to the same length as the other side because the shoes have worn and the drum also. I would screw it all but a couple turns from the bottom and try to install the drum. You can then push the drum tight to the hub a turn it to simulate actual driving and feel for shoe drag. You may need to do this several time until you feel a slight drag on the drum. With the shoes properly adjusted you should still be able to spin the drum by hand easily so you don't overheat the brakes driving down the road and cause lockups everytime you hit the brakes. Now do the other side and your finished.

10 Drum brake adjusting tips:

OVER ADJUSTING: you can over-adjust the rear brakes on a front wheel drive car very easily as the rear is light and this can cause problems in the winter when roads get slippery or even on gravel in the summer, not to mention premature wear and hot smelly smoke coming from the rear. I actually saw a rear brake job burst into flames from this! Test drive the car in a safe place after you are done and make sure the brakes are not over adjusted.

UNDER ADJUSTING: If you under-adjust the rear shoes or the shoes loose adjustment from a rusted up self-adjuster, you will gradually get worse and worse performance from the rear brakes and your brake pedal will travel to far to make you stop, wasting valuable time in any accident situation. The other under adjusted problem that can develope on FWD cars is cold shoe lock-up. Cold-shoe lock up happens when you are travelling down a interstate for many miles without applying the brakes, then (this usually only happens in the winter months, but not always) all of a sudden a deer or a car pulls out in front of you and you hammer the brakes. When the rear shoes hit the drums they are very cold from not getting any friction (drag) from the drum and guess what, they lock up the rear end, your car does a 180 or 360 degree spin out of control, I know this because it happened to me a few years ago with a FWD pontiac 6000 and you end up who knows where. I ended up stuffing my rear bumper into the rear quarter panel of a Cadillac. Adjust your brakes properly and this probably won't happen!