How do you replace rotors on a 1987 Chevy truck?

Answer 1

First you will need to determine if your truck is a 1/2 ton, 3/4 ton, or 1 ton, and wether it is two wheel drive or four wheel drive. This is nessasary because the rotors and hub are one piece assemblies on the two wheel drives, and differ with the different brake systems available by GVWR.

On either a two or 4 wheel drive truck you will first need to remove the brake caliper and brake pads from the rotor. This will require Allen keys for the 1/2 and 3/4 ton trucks, and a hammer and drift for a 1 ton truck. After the calipers are unbolted (or otherwise detached on the 1 ton) use a piece of wire (cut up a coathanger if nessasary) to hang the caliper from the frame inside the wheel well out of your way. The flexible brake lines were not designed to be put in tension, such as having the caliper dangling from them.

If you have a two wheel drive truck, you will need to remove the dust cap in the center of the rotor, using a small flat bladed screwdriver or other suitable tool. Then remove the cotter pin from the castellenated nut on the spindle. Next you can use a large wrench or adjustable jaw wrench to remove the large castellenated nut. At this point the rotor will be free to be pulled from the spindle, however care must be taken: the outer bearing retaining washer and outer bearing will be liable to fall out of the rotor/hub. If you have new hubs with races already installed, then you will simply need to buy a set of new wheel bearings, a high temperature disk brake bearing grease, and inner seals. Pack the new bearings with grease until there are no voids in the bearings. You may also lubricate the spindle with a SLIGHT amount of the grease, excess grease will only cause a mess, and will not improve bearing life. Place the new inner wheel bearing in the inner race, and then install the new inner seal, using a large socket to drive the seal into the hub. You can now install the hub/rotor assembly onto the spindle, then install the outer bearing into the assembly. Place the outer bearing retaining washer over the spindle, and against the outer wheel bearing. Then, install the large castellenated nut onto the spindle threads. While spinning the rotor, tighten the nut until rotational resistance is felt. Back the nut off, and then tighten ONLY UNTIL THERE IS NO ENDPLAY (so that the rotor spins freely, but can not move in and out on the spindle). Hopefully the castellations on the nut will be inline with the hole on the end of the spindle, and you can install a NEW cotter pin through the castellations and spindle hole. If they are not in line, back the nut off just enough to get the cotter pin through. Then bend the split end of the cotter pin to keep it from falling out. At this point you can reinstall the dust cap by carefully tapping it back into the rotor, using a large flat bladed screwdriver on the edge. If you try to install the dust cap by tapping on the center, you are likely to deform it instead of having it seat in the hub. Then, reinstall the brake caliper, and the job is complete.

If you have a four wheel drive truck, you will need to also remove and hang the brake calipers out of your way. Then, depending on which hubs you have installed, you will need to remove them from the hub as appropriate. It is suggested that if you still have the original automatic locking hubs, that you use this opportunity to upgrade them to a set of far more reliable and robust aftermarket manual locking hubs (such as offered by Warn or MileMarker etc. Beware, that there was more then one supplier of the original automatic hubs, and depending on the specific model some truck will require a conversion kit consisting of new spindle nuts). After removing the locking hubs, you will see the oddly shaped spindle nuts retaining the rotor/hub/bearing assembly on the spindle. In any case, you will need a spindle nut socket, available at most auto parts stores for purchase or rent. You will need to know if you have a 1/2, 3/4 or 1 ton truck to get the correct spindle nut socket, as 1 ton trucks use a different socket. Paying CLOSE ATTENTION to the orientation of the parts, use the appropriate spindle nut socket to remove the outer spindle nut, then remove the locking washer, then use the spindle nut socket to remove the inner spindle nut. You will need to keep these parts in the original orientation for reinstallation, as this is what keeps them from backing off the spindle. Failure to reinstall correctly will result in catastrophic damage to the parts, and possibly a loss of control of the truck, as the wheel will come off while driving. After the spindle nuts and lock washer are removed, the process is largely the same as the two wheel drive trucks. Reinstallation will also be the same as the two wheel drive with reguards to the inner seals, greasing, and inner spindle nut tightening. You will need to install the lock washer so that it is both indexed into the slot on the spindle, AND the small nub on the inner spindle nut. If a washer hole does not align with the nub on the inner spindle nut, then you can try flipping it over, or backing the inner spindle nut off just enough to lign it up with a hole in the lock washer. Then you can install the outer spindle nut, and tighten to approximately 60 lbft. If you bought new locking hubs, install them per the manufacturers instructions, and reinstall the brake caliper.