rear disks

[chuzie]

Awesome article Matt. WE are going to do this sometime this summer. I want brakes for the November run!!!

I know a raw OCR scan when I see one; way to go slacker. Let me help you out...


Lets face it, drum brakes are just too ineffective for stopping a big tire'd 4wd, especially if, like me, you have beefed up the motor quite a bit. However, with only a few kits available rear discs are not always in the budget. There is a solution to the more expensive bolt on kits, but there is one requirement; If you plan to drive the truck on the street be sure to have a qualified welder do the final welding. I cannot express this enough, it may be your life or the life of those who drive around you that you save by having some one do this step correctly.

First you need to strip the rear axle down, including pulling the axle shafts out of the housing. Grind the paint/rust/dirt off the end of the axle tube so you will have a clean welding surface. This is a good time too put on new axle bearings or upgrade to better shafts. In my case I chose to upgrade to new Dutchman 31 spline axles. These come with a slide in axle bearing retaining plate which will make the reassembly easier.

With the backing plates removed from the axle you will have a shaft with just the bearing retaining plate on it. The lug studs will need to be removed. A trip to the parts store and ask for the same size stud but with a larger portion of threads. Bring an old one with you, it makes it real easy to find the new ones. Drive the new studs into the holes in the rotor NOT the axle. Now install the rotor from in behind the axle flange, not on the outside of the axle flange (the knurled part on the stud is longer than the rotor is thick so they will stay together). Now reinstall the axle back into the housing. This step can be a little harder if your staying with your stock axles. The stock axle bearing retaining plate is meant to mount over the backing plate. You will need to cut a square piece off the backing plate (roughly the same size as the retaining plate). Install the cut portion on the shaft last so the bearing plate will mount through it to the axle. This maintains a proper preload on the axle bearings fits GM mehanic.

You should now have an axle with just rotors mounted to the inside of the shafts. Now you need to run new caliper hoses. I recommend upgrading to braided stainless steel hose, however stock rubber hoses can be used (use the same application as the caliper donor car). You can either drop long hoses down from the frame on each side or run new steel lines from the stock point on the axle and then use rubber to the caliper. I chose to add a longer braided hose at the center (stock mounting point) and new steel line out to each side. From there I used braided lines with banjo fittings to go to the calipers.

With all the new hose run you can now install the pads in the calipers, attach the brake hose. Depending on were you plan to mount the caliper you may need to bleed the system, use a block of wood stuffed between the pads and bleed the lines. Slide the caliper on the rotor, then mount the caliper to the weld on bracket. Dry fit the caliper to see what clears the best (do not weld anything yet), be sure to have the bleeders facing up. Even if you have to put the left caliper on the right side to do so. If you pump and hold the pedal with a stick (pry bars work great for this, If your helpers are in the house). The caliper will be centered on the rotor, the bracket should be on the axle tube. Tack weld the caliper on, try to be sure its solidly tacked.

Now take it all back apart again, the axle bearing and caliper should not be mounted while finish welding is being done, this could damage the seals. Run small welds as not to distort the tube or the bracket, however you do not want to use too little heat or wire speed as this could cause weak, shallow welds. Be sure to treat the welds with a rust preventive and then paint. Reassemble, bleed the calipers again.

If you want disk brakes but you also want an emergency brake you are in luck, the late 70's to early 80's Cadys had rear calipers that are the same size as the S10 calipers. However, take the e-brake cables into account when mounting the calipers/brackets. The cables will need to be run forward. I used a universal cable and tied it into the stock pedal assembly. I have since removed the caddy caliper as their e-brake holding capabilities can be somewhat less than they need to be. The Cady caliper e-brake mechanism can also be a pain to get adjusted properly and stay adjusted. (I only used one since I used to run a spool). I prefer to use Lever Lok's with the S10 calipers.