Replacing rear drum brakes

Here is an article that can help you understand how drum brakes work, properly tear down and assemble them, and identify the rear drum brake components. This brake repair is on a 1996 Chrysler Town and Country mini-van.

What you need to perform a rear brake job/repair

You will need the following parts and tools to perform this repair;

• 1-Brake shoe kit
• 2-Wheel cylinders
• 1-Hardware spring kit
• 1-Can of brake clean
• High temp brake lube
• 1-Bottle of brake fluid
• 1-Can of PB blaster
• 2-Brake spring tools
• 1-Wire brush
• 1-5/16″ bleeder wrench
• 1-Flat blade/standard screw driver
• 1- 3/8″ Ratchet
• 1-3″” extension
• 1-10mm socket

Price comparison

Do it yourself-2-Drums $40 each
1-Brake shoe kit $25
2-Wheel cylinders $13 each
1-Hardware spring kit $12
1-Brake fluid $4
Total = $147 in parts (plus tax)

Repair shop cost -$298 in parts
$240 in labor (3 hrs @ $80 per hr)
total=$538 plus tax

Important! Prepare the Vehicle for Brake Repair

For help with jacking up a vehicle and removing the wheels refer to the following posts;

Note: refer to How to use a jack and jack stands
Note: refer to Remove and install a wheel

Let’s get started on the rear drum brakes

Remove the rear drum from the axle/hub assembly.

Sometimes rear drums can rust onto the hub and extra force may be needed to remove them.

Here is the rear drum assembly with the drum removed.

In this case the customer concern is, the brakes pulse when applied at highway speeds and a vibration is coming from the rear of the vehicle.

Scenario for brake pulse

When movable brake parts age and are exposed to a variety of weather conditions rust becomes a big factor in shortening the life of these parts.
Parts that would normally move become seized and the brakes stay partially applied causing them to heat up and warp the drums. This results in premature wear and brake failure. This brake pulsation is a common occurrence for drum style brakes.
Brake drums can be machined to eliminate an out of round shape from brakes staying engaged and warping the drums. It’s more cost effective and less time consuming to replace the drums especially for the do it yourself type person.

How brakes work

If you need a break down of how automotive brakes work, refer to Automotive Braking Systems 101-Part 1

Evaluation of the brakes

The hydraulic portion of these brakes has a leak. Although it’s not a severe leak, it’s still a leak. This leak could fail with a complete and total loss of the brakes.

It’s a good thing this brake concern lead to an inspection and found this problem before it left the customer stranded or caused an accident.

Parts to Replace

Here is an itemized list of needed parts to repair this job.

• 2-Rear brake drums
• 1-Rear brake shoe kit
• 2- Rear wheel cylinders
• 1 -Spring hardware kit
• 1 –Bottle of DOT 3 brake fluid

Tear Down

Here are a few tools that are much needed to perform this job.

These are all spring removal tools which I will show you how to use through out this post.

Start by using this aerosol brake spray cleaner to help remove any brake dust that can become airborne and inhaled.

Make sure to use a suitable fluid catch/drain pan for the job.

Don’t forget to wear your safety glasses!

Once this is cleaned, start by removing the brake shoes. Remove the hold down springs and retainers.

Remove the emergency brake adjuster spring and lock.

Remove the lower spring that connects both shoes together.

Pull out the lower emergency brake pivot bar.

Remove the upper spring that connects both shoes.

Pull out the front brake shoe.

Pull out the threaded brake shoe adjuster.

When removing the rear shoe, the emergency brake cable will need to be detached from the pivot arm.

Pull the cable out of the pivot arm and remove the rear shoe.

Clean the backing plate with a wire brush

Here’s a helpful spray to use when removing bolts and brake lines to prevent damaging these components.

PB blaster is the best penetrating spray to use on rusty parts.

There are 2 hold down bolts and 1 fluid line to the brake wheel cylinders that need to be sprayed.

After spraying, start by loosening the brake line and removing the two 10 mm wheel cylinder mounting bolts.

Note:

Sometimes these brake lines are seized. To prevent braking the line and having to replace or repair the hydraulic line, you can perform this old trick that I picked up years ago.

Pull the wheel cylinder towards you. This allows you to unscrew or spin the wheel cylinder counter clockwise for removal to avoid breaking the line.

Remove the old leaking wheel cylinder.

Prepare to install wheel cylinder

Now that this is done, prepare to install the new wheel cylinder.

Loosen the bleeder screw before installation. This allows the fluid to fill up and prevent air locking the wheel cylinder when installing the brake shoes.
Install the wheel cylinder and tighten the mounting bolts.

Once installed, close the bleeder screw. Lube the six backing plate contact points where the brake shoes contact when installed.

This will allow the shoes to properly slide with no friction, hanging up, or squeaking noises.

Use a special brake lube or anti-seize for any place where metal parts rub together.

Installing the Brake Shoes

Here you will have to transfer over the necessary parts that operate the emergency brake. (Each shoe has a part to switch over) The forward shoe has a bracket that pivots.

Remove the E-clip, lube and install into the new brake shoe.

Here’s a scary find that I found during this brake job. The emergency brake parts were seized up and wouldn’t have worked if the emergency brake was used. With a leaking wheel cylinder, this vehicle was on borrowed time.

When purchasing the brake parts, make sure to get a spring kit. The old springs get weak and could break if reused. The cost is minimal and will prevent future problems.

Switch over the pulling arm from the old shoe to the new rear brake shoe and lube with grease to allow a smooth operation when applied.

Assemble the rear brake shoe and install new springs.

Lube and screw the brake adjuster inward for installation.

Install the adjuster between the shoes.

Install the spring that holds the adjuster in place.

Install the adjuster lock and spring.

Note:

If you forget or have difficulty remembering exactly where all the springs go, use the opposite side as a mirror image. This is why it’s good to only tear down one side at a time.

Install the lower emergency brake pivot bar

Install the holding spring and recheck or compare to the opposite side for proper fit.

After finishing the assembly of the rear brakes, use brake clean on a shop rag to remove the grease that might have inadvertently got on the shoes while handling during installation.

Clean the new brake drum as well. When stored at the parts store they are lightly oiled to prevent rust from forming on the metal surface.

Slide the drum in place and check for a slight amount of drag.

Note:

The adjuster can be turned manually to increase the drag when turning by hand. A good rule of thumb is to pump the brakes with the drum installed then turn the drum by hand and there should be very little effort.
When driving and operating the brakes, they are designed to self adjust as they wear in upon daily driving.

Bleeding the brakes

There are a few ways to bleed out the trapped air from the hydraulic brakes.

The first is to use a vacuum type evacuator like this standup model.

Install the hose and pump the handle. Open the bleeder screw and a vacuum will pull the fluid through the system eliminating any air that might be trapped.

The second is to use a hand held vacuum pump which operates just like the larger model.

The third way is to have someone pump and hold the brake pedal while you open and reclose the bleeder screw letting out the trapped air. Be sure to keep the brake fluid topped up when bleeding the hydraulic system and use the brake clean spray and shop rags to clean up spilt brake fluid.

Test the emergency brake for proper operation and make sure they don’t stay applied. Reinstall the wheels, torque the lug nuts, and perform your test drive.

Note:

Most brakes will take approximately 50 to 100 miles to fully seat in. For the most part, they should feel like new brakes right away.