Rear disk brakes, has anyone ever?

[sam's 72]

Has any one bought the rear disc brake kit from GMC paul or some other place? If so how did the installation go? Did every thing bolt right up? Or did you have to do some modifcation to the kit to get it to work? Let me know , cause I think I am going to go this route on the back, and go with kevelar brake linning all away around.
Sam

[1971Stepside]

I have not personnaly done the install but I know I have seen someone post that they have. They said it was pretty easy. I talked to the guys at Early Classic and they strongly recommend against putting rear disc on these trucks. They told me they had tried several and were never able to get the brakes proportioned correctly. The rears would either lock up or simply do nothing. After talking with them I decided to just stick with drums in the rear.

[Fast68Chevy]

next best thing- if not better anyways- would be to swap on factory 2.75" wide rear brakes off a donor 76-79 truck.

good luck

[sam's 72]

Hey fast,
I can go that route also, I dont know if you remember or not, but I bought the backing plates from you, for the 2.75 brake shoes in the back, I sand blasted them and got them painted, ready to go , then started kicking this ideal around about disc brakes in the back. I am replaceing the intire brake system, except fpr brake pedal.
Sam

[red71cheyenne]

Could a person make his own backing plates to work with the calipers off the front of a 71? Would this be harder than getting some off of a donor? Thanks, Jeff.

[low 84]

Originally posted by 1971Stepside
I have not personnaly done the install but I know I have seen someone post that they have. They said it was pretty easy. I talked to the guys at Early Classic and they strongly recommend against putting rear disc on these trucks. They told me they had tried several and were never able to get the brakes proportioned correctly. The rears would either lock up or simply do nothing. After talking with them I decided to just stick with drums in the rear.

ditto same here

[jiggs]

I am going with disks on the back too. Could you give more info about why they are a bad idea? Seems like it should be a good mod to me. Is it because these trucks are so light in the rear?

[Wasted Income]

Rear discs are not a bad idea. It's true that these trucks are lighter in the rear, but that is where an adustable proportioning valve comes into play. You can tweak it until you have just enough bias to keep your rear wheels from locking under heavy braking. Discs also work less to stop a vehicle because it is easier to clamp on a rotor than it is to "push out" on a brake shoe. I realize that self energizing drum brakes help, but are still not as good as properly set up discs. Also, if you do any off roading, you do not have to worry about getting water and muck into your drums. Commonly, the most difficult part of a homegrown rear disc conversion is setting up a parking brake mechanism. This is solved by purchasing a kit from a major supplier, or using a F*rd 9" that had disc brakes on it originally.

Can I be elected to an office in the disc brake club too?

-Jeff

[Low68]

I bought the rear 5-lug kit from brothers. They bought it from CPP. Lets just say that the kit sucks. I took the rear end down and got a posi unit put in and brought it home and put it all together. I put the brackets that they include(the ones that bolt the caliper to the rearend) and tried to bolt the caliper on. The hole for it wasn't lined up right, so it went in slightly crooked. I needed my truck right away and putting the old brakes back on where not an option(they were broken). I did this at the same time as lowering it and putting front disc brakes on, so to me it seemed to stop a whole lot better, but I can't tell if the rear brakes do anything or not. If you do decide to go with rear disc brakes, then I would STRONGLY recommend not going with the CPP kit. Brothers probably still gets their kit from cpp. Other than that, it includes everything you need to convert it including a non-adjustable proportioning valve. I would also recommend getting an adjustable valve. This is just my experience with these particular brakes, but some one else may have had a different experience. If you do decided to get this kit I would recommend that you check to mak sure all of the holes line up before you put it all together, if possible. If you have any more questions just let me know. Sorry, I didn't take any pics of the install. Good luck
Low68

[dmec]

the thing i dont like about aftermarket brake kits is the caliper bracket is cut out of a piece of plate and offers no support for the caliper to stop it from cocking. the original gm backing plates supports the caliper a lot better. i have just finished adapting cad seville rear disc onto a truck rear but dont have it installed yet so i dont know if they make a difference yet. i just like the looks and brake jobs are a lot easier. im taking pictures of what mods i made to install cad seville brakes and plan to put step by step info on the board for all to see. it takes a little work but is alot cheaper than the kits. hope to have the info on the board within the next week if interested.

[dmec]

just a sample

[jiggs]

You bet I'm interested. Thanks for taking the time to take pics and post the results!!

[Shane]

here is a pic of a 12 bolt with the Caddy conversion on it. 77 Cadillac Seville parts.

[RON WOODGEARD]

SHANE,

Will you explain the conversion, PLEASE!!

RON

[Shane]

Ron....here's a thread from a while ago that might help.....

http://67-72chevytrucks.com/vboard/s...threadid=13484

Hope this helps......let me know if I can help any other way....

[Shane]

left side.....

[Shane]

right side....

[dmec]

hey shane ya got any pictures of the backing plates bolted to the backside of the axle flange? i thought of doing it that way also and figured out a way to use 3 bolts, but i decided to use all 4. i went to your post and found it interesting. i can expand on your knowledge a little bit. the 76/79 caddy brakes had a couple different configurations. they came either big or small frame calipers depending on year. they are the same size as the front calipers but have a smaller piston for proportioning. dont want to get in to this too deep now. im going to have pics and better explanation when i post my conversion. my backing plates bolt on from the front and use all 4 holes and the caliper is centered in the rotor.

[Shane]

hey dmec.....when i tried mounting the bracket on the front, I could not get an alignment between the caliper and rotor.

Did you put spacers behind the rotor to move it out? I thought of this, but decided i would rather have the bracket spaced "in" as opposed to having the rotor spaced "out." Does that make sense to ya??

Thanks!

[brennecke]

Are those open or posi gears in the cads? If they are posi, this could solve all my gearing problems!

[Shane]

The Cad rear-ends are the smaller 10 bolt variety.