We have discontenued the manufacture of the 1/2 ton disc brake set due to low volume of sales.
Price: $495.00 plus shipping and two serviceable hubs.
Our disc brake conversion kit for WC1/2 ton Dodges includes the following:
1. 2 ea. 3/8" plate steel caliper brackets.
These bolt directly to the knuckle with no modification or welding required.
2. 2 ea. hubs with rotor mount flanges.
Welded in place and machined.
3. 16 ea. 5/8" NF X 1" grade 8 socket head bolts.
For attaching the rotors to the hub rotor flanges.
4. 10 ea. 7/16" NC X 1 1/4" grade 8 bolts and lock washers.
For attaching the caliper brackets to the knuckle.
5. 4 ea. new bearing races installed
You will need to purchase the following locally:
1. 2 ea. 78 - 87 GM 3/4 ton 4X4 rotors: (about $30 each)
2. 1 ea. 71 - 78 GM 3/4 ton 4X4 right caliper (about $60 including core charge)
3. 1 ea. 71 - 78 GM 3/4 ton 4X4 left caliper (about $60 including core charge)
Disc brake installation instructions
General information
I have tried to make the installation of this disc brake kit as easy as possible. No grinding, drilling or modification to the knuckle or calipers should be required. We install each set on a test fixture and check them both for proper fit and with a dial indicator for run out (the run out in thousands of an inch is written on the face of each rotor flange.)
Axial (lateral) run out should be .006" or less, radial run out can be as much as .010" without causing problems. Ours are .002" to .005" measured at the outside edge of the rotor (12.5" dia ) all of this assumes that the runout on your rotor is 0.000". Be sure to mount the hub with the lug bolts marked "L" on the left side of the truck and the one with "R" on the right side. Please refer to your particular trucks shop manual for proper procedures for removing and installing original parts i.e. hubs etc.
Additional parts and tools needed
2 ea. 78-87 GMC 3/4 ton 4X4 rotors
1 ea. 71-78 GMC 3/4 ton 4X4 caliper
1 ea. 71-78 GMC 3/4 ton 4X4 caliper
You will also need a 1/2" socket type allen key for tightening the rotor bolts.
Wheel stud installation
We are no longer able to include new wheel and axle studs with our brake sets. Because of the poor condition of the ones that have been returned to us we have run out of new ones and can not find a reliable source for them.
You will have to remove your old ones and replace any bent or damaged ones as best you can from other hubs or one of the parts suppliers. If you use a hammer to remove them be sure to install a wheel nut even with the end of the bolt so that you don't damage the threads.
Before installing them in the new hubs we have sent, you will need to install three of the 15/16" snap rings provided on each wheel stud. This takes the place of the old brake drum and keeps your lug nuts from bottoming out on the bolt shank.
Use an aluminum drift about 1" square by 12" long and a 3 lb. Hammer to drive the wheel studs into their holes. You must protect the rotor flange edge from the drift this is easily done by wrapping the area that comes into contact with the flange with a 1/8" layer of duct tape. You may also want to cut a donut out of 1/2" plywood to protect the face of the rotor flange incase you miss the drift when hammering the wheel stud in. The slightest defect in the surface of the rotor flange will cause the rotor to wobble.
The hole and stud diameters vary and if a stud is too tight or loose for one hole it might fit perfectly in another. If you have dial calipers you can measure to begin with and make this process easier. Dial calipers are available from places like Harbor Freight for as little as $10 and are very useful to have around the shop. If the fit is tight you should lubricate the stud before inserting it. If the fit is too loose, use some loc-tite of the permanent variety to secure it so it doesn't back out later.
The axle studs can be removed by double nutting them and using a wrench to remove and install. If they are stuck a pair of vice grip pliers will usually break them loose after soaking overnight with penetrating oil and applying a little heat from a propane torch.
Installation of front brakes
The photos in the following instructions are of an M37, the installations are almost identical.
1. Remove the old hubs, drums, shoes, wheel cylinders and backing plates from the knuckles. It should now look like the Photo below. If your front axle hasn't been serviced lately this is a good time to do a complete tear down and replace the seals and bad bearings.
2. Install the caliper brackets with the ears pointing rearward and inboard (they can only be installed one way). Use the ten 7/16" NC X 1 1/2" bolts and spring lock washers in the ziplock bag marked "bracket bolts" to install them on the knuckles. Torque bolts to 50 ft. lbs. See photo below
3. Place the rotors on the hubs as shown below.
4. Find the ziplock bag of sixteen 5/8" NF X 1" socket head bolts that is marked "rotor bolts" and use them to fasten the rotors to the flange ( make certain that there are no burrs, dirt or paint between the rotor and the flange). If the rotor that you are installing is a "tight fit" it may be necessary to temporarily install the bolts and use them to seat it (tighten the bolts evenly going from one to the other). Before installing the bolts clean them and the threaded holes with lacquer thinner to remove any oil. Then apply a couple of drops of lock-tite to the threads of each bolt prior to installing them. Use a 1/2" socket type Allen key on a 1/2" drive torque wrench to torque the bolts to 80 foot lbs. See photo below. ( Use a wheel inside down on floor to hold the hub and rotor while torquing the rotor bolts).
5. Install new inner hub seals and the snap rings that retains them. Pack the bearing cones with high temp. disc brake grease (also the entire interior of the hubs). You should read the appropriate chapter of your trucks maintenance manual for proper installation of the hubs and their nuts.
6. Next install the calipers with their pads in place (make sure that the bleeding nipple is pointing up and the cylinder is to the inside).
7. Insert the caliper pins from the back side through the calipers, then through the 7/16" NF threaded holes in the caliper bracket ears, under the inside pad hooks, through the holes in the outside pads, and finally through the outer caliper holes. After you tighten down the caliper pins against the caliper pin bushings it should look like this. Be careful not to cross thread the caliper pin. Use your fingers to start it as you wiggle the opposite end to get the alignment right. Note: if the caliper seems to be too far out for it to fit over the caliper bracket ear, this may be caused by an outside pad that is too thick. If it is only a few thousands too thick use a disc or belt sander to remove the excess. Before doing this make sure that the problem is not caused by an improperly seated outside pad.
9. Below is a close up of the caliper pin installation, notice how the inside pad has a hook that rides on top of the pin. Failure to install both of these hooks as shown may allow the pad to drop down out of position resulting in partial or complete brake failure.
10. At this point you need to hook up your new disc brakes to the brake lines. This can be accomplished in a couple of ways.
1. Use your original type flex hoses and banjo bolts on the front. In this case you may have to widen the slot in front of the caliper inlet port (the original Dodge hose is too large to fit through it). This can be done with a small file or dremel tool. Be careful! if you damage the inlet port area where the copper crush washers go the caliper is ruined.
2. If your existing original hoses are old and need changing anyway or if this is a rear installation (flex hoses need to be purchased) then move on to the next section for a short lesson in brake hoseology. Hooking up to your hard lines. The following brake parts can be purchased from a Carquest or NAPA parts store.
