Loosing the drums on a 68 C-20

[panhandler62]

There are lots of high-end rear disc conversion kits available but I thought I would detail the path I took. I know that I was thinking that a disc brake conversion would be a whole lot more complicated so this may be helpfull to someone else too.

My truck has the HO52/72 rear end. To get started you need to pull the 8 bolts in the axle cap. You will want to put a pan under the mess because some rear end goo is going to run out.

When all 8 bolts are out pull the axle out and set it aside.

Clean the goo away on the first nut and find the tabs on the lock washer that are bent over to secure the outer nut. Bend them back out of the way and remove the outer nut. An axle socket is the proper tool to use but there are any number of improvosations that work also.

Once the outer nut is off grab the lock washer with a pair of pliars and remove it. Grab your axle socket again and remove the inner nut and remove it.

Hopefully you will be able to just grab the drum and pull it off at this point. If not, well, have fun. One of mine came off with no drama at all, the other required a gigantic claw puller and a pry bar because the brakes had built up such a huge ridge.

Loosten and remove the brake line and all the brake parts. The hubis attached to the drum and has a small backing plate that slips over the anxle housing that can be pulled off and set aside.

The backing plate is held onto the axle with 4 bolts. I had to use a combination of PB, an impact wrench and a propane torch to get mine off. You'll want to clean up these 4 bolts and chase the threads on them with a die so you can re-use them. With the bolts out the backing plate can be tapped off the axle housing. Run a tap through the holes until it threads easily to clean the rust and what-have-ya out of them.

The first thing to go back on the axle is a bracket for the caliper. RuffStuff is where I got mine. There are other sources. A pair shouldn't cost more than about $50. Figure out which of the 2 available angles (ok, there are 4 possible angles, but I don't think you want your brakes on the bottom!) you want the calipers mounted at and tap the brackets into place and secure them. (make sure there are facing the right side out!)

Tap the inner cap for the hub back on the axle (go easy, it's kind of flimsy.)

Now-- set the drums open end down and bang all 8 studs out. The hub is now seperated from the drum. This is the best time to clean and repaint it, but I guess you don't really have to. lol

set the hub, outer end down, on a work surface and line your new rotors (front K-20 rotors from a 75 or any other truck that matches the part number) up with the stud holes. If you are using aluminum wheels you are going to need longer studs. I found part number 98266 studs at Advanced.. they are 1/2" longer than the originals.

Once you have all 8 studs tapped in place on each hub/rotor assembly you can slide the hubs back onto the axle housing and re-install the axle nuts and lock washer.

Slide the axle back in and re-install the eight bolts.

Several calipers will work. I'm using the front calipers off an 86 truck. You won't have a parking brake any more unless you use calipers with a brake built in (such as the calipers off a Caddy) but you can use other options, such as a shaft brake.

You'll need some brake plumbing, but there are so many ways to go there I'll leave it out of this.

All in all, pretty simple and not real expensive:

Calipers...$36 to $120 (depending on what you use)
Rotors.....$85
Studs......$48
Brackets..$50

You will want to use a different proportioning valve also. You can get one from any number of sources. I will be using this:
http://www.jegs.com/i/Wilwood/950/26...ductId=1284815