Rear Disc Swap

[Markassbauer]

I've been running this swap for almost 4 years now. Here's what I did;

Grab rear lower control arms from a 2000+ lesabre or bonneville, cut off the square part where the hub bearing and caliper bolt up, have a machine shop mill the cut side flat, and drill threads out of hub bolt holes. Use these pieces as spacers between rear hub bearings and knuckles attach with applicable length and diameter hardened bolts and nuts and viola! You can mount calipers!!! Calipers will mount towards top of wheel well, and you will need to use 2000+ bonneville/lesabre calipers, pads, rotors, hoses and hub bearings. You will need to add a short piece of brake line on each side to reach the new hoses and also matching ABS pigtail connectors to match up to the new hub bearings.

[95naSTA]

Sounds sweet. Any pics? Parking brake solution? Do you lock up the rears under any conditions?

[Markassbauer]

Never had a rear lock up situation EVER. Once I get my car back to my house I'll take pics, not really sure why I never did. And no parking brake installed for my setup, but I don't think there would be much issues using or modifying the stock cables to work. Worst case scenario use cables from the donor car.

[Markassbauer]

http://m.imgur.com/gallery/ZtnZH58



http://m.imgur.com/gallery/ZtnZH58

[95naSTA]

Next time you have a wheel off I would really be interested in seeing how all the parts mesh together.

From your description I feel like if I had the parts infront of me I could probably figure it out but without anything visual, no idea.

[Markassbauer]

As soon as I get the car back I'll take pics. It's SO simple, and interferes with nothing. I wasn't sure if it had been done before, but I looked up rear suspension and brake schematics for ALL the FWD GM cars I could think of while I was still a parts guy, and this was the ONLY simple, cost effective option I came up with. And worked like a charm plus it's as easy as changing rear hub bearings, no extra work once you've got all of the needed parts.

[Markassbauer]

Alright, anybody who's interested in this swap, I just did the same swap on my old ladies '89 6000LE wagon. While I had the necessary pieces cut off from the donor control arms to take to my buddy to have milled flat, we traced the pattern on some billet pieces and had a few sets made on a CNC as well as saved the program so we can make these in the future with ease rather than buying and ripping off junkyard control arms, cutting the plates off and having them milled. I plan to sell these adapters in the future if there is interest. Will literally fit ANY fwd GM vehicle that uses that 4 bolt rectangular flange rear hub bearing and I have a list of vehicles to get donor brakes from.
This swap will most likely require 15" minimum wheel size considering the rotors are 11".

[00Beast]

Like Mike said earlier, pics of the setup would be fantastic, with a wheel off, even maybe with the brakes and hub off, so we know what is bolting to what.

[Markassbauer]

I took all of those pics this time! I have no idea how to or if I can post them on here, but I can email or text them to anyone who'd like to see, or if I can send them to another member if they'd like to post them in this thread, that'd be great!

[00Beast]

http://www.pontiacbonnevilleclub.com/fo ... 46080.html

That's the easiest way. Seems like you use imgur already?

[oceandaemon]

I would be super interested in getting a pair of those fabricated adapter plates if you are still considering selling them off.

[Markassbauer]

I think this will be the link to the pics, bear with me guys...

https://imgur.com/gallery/yOXXH

[Markassbauer]

And yes I will/can sell sets, I figure $100 is fair. 2 plates plus the 8 longer mounting bolts that are required.
All other hardware/parts is factory stuff from the disc brake donor car.

List of donor cars are;

2000-05 Buick LeSabre
1997-05 Buick Park Avenue
1992-99 Buick Riviera
1993 Cadillac Allante
1994-99 Cadillac DeVille
1992-02 Cadillac ElDorado
1992-97 Cadillac SeVille
1995-03 Oldsmobile Aurora
1992 Oldsmobile Toronado
2000-05 Pontiac Bonneville

Just make sure you get all the parts from same year/make/model.
You’ll need to grab the hoses, calipers, brackets, mounting bolts, pads & rotors.

[oceandaemon]

Do you notice an improvement in braking performance with this mod compared to the original drums?

Also did you have to adjust or remove the proportioning valve for the rear brakes now that they are disc and shouldn't (I think?) need it?

[Markassbauer]

A world of difference in braking performance. Feels like a modern car when braking now, no more harsh drum braking from the rear that was unpredictable in the pedal and would on occasion want to lock up.

No proportioning valve change necessary, I’ve done rear disc swaps on Chrysler’s as well and never needed to change proportioning valves. I’m sure many of internet users would disagree with this practice, but I have vehicles in my driveway that prove good everyday.

[oceandaemon]

Well I am sold. How soon would you be able to sell one of the kits?

[95naSTA]

Thank you for posting the pics and info.

[Markassbauer]

No problem at all! Hopefully it can help some folks out there! It really is an easy swap and a “why not?” Upgrade. Especially if your drums need servicing anyway.

If anyone has ANY questions about it or would like to buy the billet plates instead of buying used control arms, a bunch of sawzall blades, spending a couple hours cutting them up, then having the backs milled flat just let me know.

Thanks guys.

[oceandaemon]

Could you PM me about how to purchase a pair of those adapter plates? The forum will not let me send a PM at the moment because I am too new of a user but I think it will still let me receive and view ones you send me.

[Markassbauer]

PM sent!