Replacing the rear brakes on a 1989 dually is very similar to replacing any drum brakes except for a few minor details. One, there are two wheels on each side to be removed instead of one. Two, the axle must be removed to get the brake drum off (No biggy, relax.). And three, the parts on a dually are bigger and thus heavier than on most cars and trucks, so use caution when removing heavy parts.
The steps for replacing the rear brakes on your 1989 Chevrolet dually are listed below in complete detail with photo’s too!
Tools You Will Need
- Sockets and a socket wrench with an extension.
- Breaker bar.
- A 2-ton floor jack.
- Jack stands.
- 2 Flat head screw driver.
Parts You Will Need
- New set of brake shoes.
- Brake parts replacement it (recommended).
- Brake grease.
- Brake cleaner.
First we’re going to remove the wheels.
- Park the truck on a clean, level, surface.
- Chock the front tires well.
- Choose which side your going to start with and crack the lug nuts loose with your breaker bar and extension. The dually wheel set-up does not allow access with a standard socket. An extension must be used. Employ a support of some sort for your extension tools to work properly (See photo below).
- Once the lug nuts have been cracked loose jack up the side your working on, or the whole rear end, your choice. And set it down on jack stands.
- Remove the lug nuts the rest of the way and set aside in a safe place where they won’t be lost.
- Remove the two wheels from the axle and set aside or under the truck for added protection in case the truck falls. Both of the wheels should slide off one after the other. If the inside wheel doesn’t slide right off you can tap it with a hammer to break it loose. Do NOT tap on the lug nut bolts.
2nd The Axle Bolts & Axle
- Remove the 8 bolts on the end of the axle. These bolts help to keep the axle in place. Use a large screw driver or other item to hold the drum from spinning while you crack them loose (See photo’s below).
- Once these are removed the axle will slide out (See photo). Set aside in a safe, clean, location.
- The brake drum is still held in place by the thrust washer inside. Use needle nose pliers or a flat head screw driver to remove the retaining clip (See photo’s).
- There is a key that the retaining clip was holding in place. Use a magnet, or tweezers, or maybe the needle nose pliers to remove the key (See photo’s).
- The thrust washer is removed by turning it counter-clockwise until it comes off of the threads (See photo’s).
3rd We Will Remove The Brake Drum
The brake drum is ready to come off now that the thrust washer and axle are out of the way. Pay attention to where your fingers are on the drum and what is directly under it (toes!). Leaning into the wheel well pull the drum towards you. It should slide right off and it can be heavy!!
If the brake drum doesn’t slide off access the back side of the brake plate. There is a small access hole on the back of the brake plate, on the bottom. If it is not open, use a screw driver and hammer to break out the little metal window. Slide one screw driver in to lift the adjusting lever off of the brake adjuster and twist the sprocket to remove the pressure of it pushing on the brake pads. The left side twists upwards to unscrew and the right side twists downwards to unscrew I believe.
Once you have relieved the brake adjuster the brake drum should slide off. If it still won’t slide off take a hammer and tap around the circumference of the brake drum until it does come loose. Set the brake drum aside making sure that dirt does not get inside of it.
4th Now You’re In! You Can Start Replacing the Brakes.
There are a couple of different places you can start removing the brakes at, top, or the bottom. I’ve started at the top only to have the assembly fall to pieces in my hands, so now I always start at the bottom. It’s just a matter of preference. I prefer the parts to stay put until I want them to come apart.
Caution: There is asbestos in this area. Do not blow out dust with compressed air or your mouth!
- Starting at the bottom, remove the blue shoe return spring. This will allow the start wheel to be removed.
- Remove left shoe retaining spring using a socket on an extension to press and twist it in. This will release the front shoe.
- Swing the shoe up until the tension on the top yellow spring is released and remove it from the assembly.
- Do the same to the right side allowing the brake cable to remain attached.
- Clean the housing with brake cleaner and a toothbrush.
The 5th Step Is Install Your New Brakes!
- Dab some of the brake grease on the wear points around the brake back plate. There should be 6 specific spots that wear easily and need grease applied. At the 1 o’clock, 3 o’clock and 5 o’clock positions, and continuing around the next one is the 7 o’clock position, 9 o’clock and lastly 10 o’clock.
- Put the new rear springs on the new brake shoe. The 1989 dually brake has an additional attachment. The animation below demonstrates how this additional wire attaches.
Once you attach the above illustrated springs and hooked them on to the top post, bring the shoe down into position and attach the shoe retaining spring. The photo’s below detail how the push pin works to hold the shoe in place.
Once you have the rear side shoe attached and pinned, do the same for the front shoe.
Make sure the wheel cylinder plugs (Coming out each side of the cylinder) are properly lined up with the brake slots made for them to sit into.
Attach the spring at the top of the brake shoe to the pin at the top and rotate the shoe downwards while keeping the top in position.
Place the parking brake strut into position with its spring when you lower the shoe down.
Attach the hold down pin.
Screw the adjusting star into its smallest position where you cannot see any of the threads. Set it into position at the bottom of the brake and attach the new blue brake return spring at the bottom.
Great job! This brake job is almost done! Now let’s put it back together!
6 Putting The Wheel Back Together
- Make sure the brake drum is clean inside. If not, wipe it clean. Only use brake cleaner or warm soapy water! Then, carefully lift it into position of the axle. It should slide on easily. Be careful not to damage the bearings inside the brake drum neck. If the brake drum won’t fit over the new brake shoes, compress the shoes by pressing them inward and make sure the star adjuster is at its smallest position and try again.
- When you have the brake drum back on it’s time for the thrust washer, “key” and retaining clip. The thrust washer needs to be carefully screwed back on the axle. Don’t force it. It may take a couple of tries to get it to start on the threads. Once it’s started it will screw on very easily.
- Snug the thrust washer on but don’t over tighten it. Line up the cut-outs so the “key” will fit back in and then attach the retaining ring to hold the “key” in position.
- Grab your axle, wipe it down to remove any dust or debris that may have got on it, and slide it back in. When it’s almost all the way in it may bump up against something. Take your time!! Twist the axle, make SURE it is level so it will fit back into the gear. It will suddenly catch its spot and drop into position if you’re patient.
- Now attach the 8 axle plate bolts. Check your specifications but I believe it’s 115 inch lbs tork on them.
7 Adjusting The Brake
This is a good time to adjust the brake adjuster. Remember the Star adjuster at the bottom of your brake set-up? You can access that adjuster like you did in step 3 to release the brake shoes from the brake drum. Now, you WANT the brake shoes up against the brake drum, just enough to cause a slight drag. To do this:
- Ensure the front wheels are chocked well.
- Move the gear shift inside the truck to the neutral position. Pay attention if the truck tries to roll. You don’t want it falling off its jack stand, especially if your under it adjusting the brake!!
- If your chocks held the front wheels in position leave the truck in neutral and go back to the wheel you were working on.
- Turn the wheel drum by grasping a mounting screw and turning it or turning the brake drum itself. Do you hear any drag from the brake shoes? Probably not, you just put them on. You want to hear, or feel, a slight drag.
- Using a flashlight and one flat head screw driver access the hole on the back of the brake.
- For the left side I believe the Star Adjuster will be pushed downward from the access hole. Shine your flashlight into the hole. Can you see the star adjuster inside? It should be right there.
- Put your flat head screw driver into the access hole and push the Stars points downward so the brake shoes will be pressed outwards.
- Have an assistant, or yourself, turn the brake drum. Any drag yet? If not, turn the Star adjuster a few more turns until you hear a drag on the brake drum and you will begin to feel some resistance when you try to turn the brake drum. Once you feel or hear the shoes contacting the inside of the brake drum, stop. That is perfect!
8 Put Your Wheels On And Take It For A Spin
Put the tires back on. First the inside tire, then the outside tire. Don’t mix them up. The rim is fashioned in a way that they will not go on properly if you have them backwards (See the photo below).
- Put the wheels on and don’t forget the metal plate.
- When you put the wheel cover on make sure the holes line up.
- Put your lug nuts on using the socket and extension. Torq the lug nuts to 140 ft/lbs.
- If you have another hub cover put that on now too using a soft mallet.
Test the brakes. If they have resistance take it for a test drive. If the pedal feels too low you can always go to that adjusting window and turn the Star adjuster more to create more contact between the shoe and the drum but don’t over tighten or you’ll be wearing down your brake shoes because they are constantly braking! Good Job!