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 biggey, relax.). And three, the parts on a dually are bigger and thus heavier than parts 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 (An extension is a must due to the lug nuts position deep in the wheel well).
- 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 kit (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 you’re going to start with and crack the lug nuts loose with your breaker bar and extension while the wheels are still on the ground.. 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 you’re 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 first wheel and set aside. The second wheel may very well have begun to come off the axle just from the first wheel being removed. 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 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!). The drum is heavy! Fingers and toes can be easily mashed when this heavy drum is removed. Pay attention where your digits (digits = fingers and toes) are. Leaning into the wheel well pull the drum towards you. It should slide right off!
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 a 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 star wheel to be removed.
- Remove the 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. They can be difficult to line-up and secure so take your time of course. Use a long socket to set on the spring with the metal cap. Put the pin through the back of the brake wall. Press the socket in until the pin goes through the hole of the metal cap, then twist the socket 1/4 turn to lock the pin in position. 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 as you place the brake shoes and pin them.
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 with your hands. Make certain that the star adjuster is at its smallest position. Then try to slide the drum over the brakes 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 fell on it, and slide it back in. When it’s almost all the way in it may bump up against something. The something is the access hole, the bottom, or maybe side, or top of it. You want to go inside the access hole. Take your time!! The axle must be level to achieve this. 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 torque on them.
7 Put The Wheels Back On
Now you’re ready to put the wheels back on. Put them on in the same order you took them off. When you set the wheel on hold it, or have someone hold it for you so it won’t fall off while you grab the other wheel. Put the plate on and the chrome hub decor if you have one and then the lug nuts to hold this all on. Tighten the lugs as much as possible while the wheels are in the air. You will snug down these bolts when you take out the jack stands and set the truck down, so for now snug them down. I like to turn the wheels as I snug down the lugs because there is a lip they can catch on if not centered exactly which, when lowered, the may or may not slip over. If they don’t right away, they will someday, and cause suddenly loose lug nuts. By turning the wheel as I put and tighten the lugs the wheel goes on centered and won’t catch this lip.
8 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 still chocked well.
- Move the gear shift inside the truck to the neutral position. Pay attention if the truck tries to roll when you do this. You don’t want the truck falling off its jack stand, especially if you’re under it adjusting the brake!! If it starts to roll, rechock the front wheels better!
- When you can put the truck into neutral, and it’s not rolling at all, go back to the wheel you were working.
- Turn the wheel drum by grasping the wheel and turnin it. Do you hear, or feel, any drag from the brake shoes? Probably not, you just put them on. You want to hear, or feel, a slight drag as you turn the wheel.
- Using a flashlight and a 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 wheel. 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 wheel. Once you feel or hear the shoes contacting the inside of the brake drum, stop. That is perfect!
Complete The Steps On The Other Side Now.
Take It For A Spin!
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!