Hello, I am seriously wanting to convert to rear disc brakes on my 77 Highboy
4x4 with a Dana 60 rear. There is a guy on Ebay that sells the special backing plates for about $60. He says that you use 75 3/4 to Cheby front calipers and rotors if you don't hook up you e-brake which is pretty cheap.

But, I want to use my e-brake, so he says you have to use 76 to 78 Cadilac Eldorado rear calipers and he don't think the existing e-brake cables will work.
Has anyone did this conversion? If so, what all am I up against? Any adivice will be appreciated. I know that www.blackbirdscustomtrucks.com sells the whole e-brake kit but, it's about $500.

Thanks A Bunch

 

Theres a article here on the conversion done on a dana 60 rear in a 79 bronco he used the cadillac calipers and got the stock e brake cables to work. http://www.off-road.com/ford/bigbroncos/tech/reardisc/

 

Thanks for the link. I'm still debating on what to do. I've got new wheel cylinders, shoes, and had my drums turned on the back. My braking is much better still yet, after installing a 78 F350 2WD booster and master cylinder. That in it'self is a big improvement.

I might wait till my rear shoes get thin and then do a rear disc conversion. I wished there was a rear disc kit that could be bolted on without any welding and still be able to salvage the e-brake with the existing cables. Oh well, I guess you can't have it all.

Thanks Sa Much!!

 

There is a company called TSM Manufacturing (www.tsmmfg.com) that sells a bolt on kit that includes brackets, bolts,and rear rotors for $279.95. The kits come with detailed instructions and are easy to install. They can also tell you hoe to make your e-brake work.

 

Thanks for the reply. That's a good thought to chew on. I kind of like the idea of buying my own calipers and pads at the local parts house so I can get lifetime warranty. The tsmmfg kit might be the way to go. Thanks a bunch!!

 

The trouble with e-brake kits is that it's getting VERY hard to find the complete Eldorado calipers that aren't missing the e-brake lever. I'm running Blackbirds rear discs and love them, but no e-brake for me right now. I've got an automatic so I really don't need it. I think I'm going to install line lock for when I need to brake it for short periods of time. Of course line lock is not something you actually want to use as a regular parking brake.

I have no experience with TSMMFG but another guy posted recently that he used their kit and they were the only ones who offered replacement rotors. They wanted a ridiculous price for new rotors, almost as much as the complete kit. If you do the Chevy caliper setup you can get new calipers and rotors anywhere and they're CHEAP.

 

I'm running the same setup that you are minus the twin stick shifters. From time to time, I pull a 16 foot trailer with either a tractor or a lot of green oak wood on it and have to park on hills sometime. I'm just a little leary of not having a parking brake. I remember a friends Blazer from highschool with an automatic with big tires would start making this awful noise as it slipped down hills while in Park.

Who makes the line lock and is it very expensive, or much hard to put on? Would it hold as a temporary parking brake Thanks!!

 

Howdy 30over. I don't know if you're familiar with how automatic transmissions work but the parking lock in the tranny can't "slip" at all. I suppose if you had enough force you could snap the rod that locks the tailshaft right off but then there would be nothing to stop it from rolling at all. The only thing that could allow a rig with an auto tranny to slip on a hill like that is if you have an open diff and one tire has poor traction. The tire with less traction could possibly slip backwards and allow the tire with good traction to move down the hill a bit.

Line lock can be ordered from Summit, Jegs, Napa, any performance parts center really. It's used by racers to warm up their tires. Basically all it consists of is a solenoid you put in your brake line and a switch or button to operate it. Usually a racer will put it in the line to their front brakes. You step on the brake pedal and activate the solenoid. When you let off the pedal it'll release pressure to the rear brakes but the solenoid holds the front brakes firm. This makes it easy to do a burnout. For us, as a "parking" brake we could use them on the front or the rear brakes. You'd need to hook it to a constant power source so they did't release when the ignition was turned off. However, since the solenoid is a 12 volt accesory it will eventually drain the battery and release. I think they'd be great for an hour or so but I wouldn't chance leaving it overnight.

But since we're talking about line-lock devices I will say that you can also get them in a manual valve which mounts in your cab. We use this for a parking brake on our forklift. It's just the same as the line lock, stand on the brake pedal, turn a lever and let off but the pressure is held to the brakes. With the valve it never releases. The only negative to this would be IF you had a slight leak, either in the valve or at the wheel it would bleed off pressure. That being said I can leave the forklift parked for weeks at a time and it holds just fine . . . as long as there are no leaks there's no problems.

While I'm blabbing about parking brakes anyway, if you have a 4x4 with the NP205 transfer case you can also buy a driveline mounted e-brake that bolts to the transfer case and uses a rotor and caliper on the driveline. Highangle Drivelines sell these kits. HOWEVER, this would only be advantageous for a manual tranny. With an auto it's really redundant as you're already locked at the driveshaft. And with one of these driveline brakes you're still at risk of the scenario I spoke of above where 1 tire on loose or slippery surfaces can allow the truck to move when parked. No, it's not a likely scenario but it could happen. Btw, last thing I'll blab about while I'm blabbing here, even with an auto in park or a manual in gear, it really sucks if you're on a slight hill and you jack up one side of the truck without chocking the opposite tire. As soon as one side picks up the truck will start rolling.

 

One more thing... folks keep calling it a "parking brake" while the other use is a manual "emergency" brake way to stop when the hydraulic system fails, rare but if it happens you'll appreciate a driveline setup or calipers with manual "parking brakes" built in. :-)
Just my 2 cents,
Jon
Poway, Ca
Ps. I have all the parts rotors,brackets, 78 caddie calipers, now I just have to find the time to install them...

 

I was through this thread on the rear disc conversion. I'm looking at doing something similar, but I can't find a good source for the caddy calipers you (and others) have used. I have a 1990 trans am that has rear disc with parking brake and I wondered how different the 2 calipers are. Could you give me an estimate of the pad area on the caddy, as well as the caliper piston diameter?
I appreciate the help
Corey