Uplander rear disc brake upgrade write up

[shocker]

Here is my write up on uplander rear brake conversion on 89 cutlass ciera. First is of course to get rid of the drum brakes off the axle. The bolts that hold the hub to the axle are torx head t-50. Once thats out of the way I ended up getting rid of the metal brake line and the short rubber line since I was mounting the calipers to the front of the wheel. Now if you mount the calipers to the rear you probably don't have to get rid of those lines just modify the metal line. Now the brake lines I used are the front driver side brake lines for 89 cutlass ciera. That happened by chance when I went to parts store to get some Caddilac rear brake hoses to try and they didn't have any so I firgured I would try the front brake hoses for the ciera. They actually work out great cuz where the hose connects to the metal line it fits into the bracket like it was made for it as you can see in the pictures. Then caliper bracket, disc guard cover and then Uplander hub. I ended up getting longer grade 8 bolts to bolt to the axle but will have a buddy of mine weld the caliper bracket to the axle to be safe. Then install caliper on bracket and the new brake hose has a nub thats needs to be grinded off as seen in the pics so it will fit the caliper. Then bleed the brakes and done. As you can see the rear discs dwarf the fronts. Not the greastest write up but if have any questions feel free to ask. Oh an with this set up it pushes the wheels out about 3/8 of inch on both sides cuz of the caliper bracket on the axle. Don't think 15" wheels will work with this atleast as to be 16".

[turbokinetic]

Thanks for the good information! It's hard to see because the software (for some reason) shrunk your pictures down to about a 2x2 inch size.

That Uplander, is that a GM vehicle?

Also, how is the proportioning? If you jack the brakes to the floor, do the front wheels lock first? Just curious!

Ive got one last set of STE disc brakes for my 86 Buick GS but after that I will be looking at other options.

Thanks,
David

[Duke George V]

That Uplander, is that a GM vehicle?

Chevrolet Uplander, the most recent version of the U van. I think you can only use the 2005, because GM switched to a six lug hub for some reason in either '06 or '07.

[shocker]

Think I fix the pictures somewhat don't know why its not putting up the actually pic but hopefully the link works. Proportioning seems ok, if you jam on the brakes its nice and smooth, its better then having the drums lock up like it was doing. Now for my taste it seem like the fronts are under sized. That wil be the next project to see if I can make olds intrigue 12" front rotors to work somehow. Yes only the 05 Chevy Uplander had the 5 bolt.

[JoshB]

2005 Pontiac Montana SV6, Saturn Relay, or Buick Terraza probably the same?

[Pontiac6ksteawd]

Yes, and no...

Not sure the Buick Terraza will work, as the whole rear suspension and brakes on that car are different. More than likely will also have to come off a NON-AWD, as they have the same rear suspension and brakes as the Buick Terraza. Someone would have to look at them a bit closer..

Another thing is, what are you doing for a parking brake now?

[shocker]

At the moment I don't have a parking brake but do have the cables. Will put them on when I lower it soon. Also will take pics of that.

[billkandi]

Any issues with bias or pedal effort?

[shocker]

No issues and pretty effortless and smooth

[Century7667]

...ever get the parking brakes working?

Ken T.

[lemons bob]

I would definetly work on upgrading the fronts. I'm guessing if you ever had to do a panic stop the back will lock up before the front and that is a dangerous because it will probably make you spin.

What size is the uplander rear disk setup. Later U-van brakes were larger and I've heard of people using some of the F-body brakes on some FWD gm cars which are also much bigger than stock.

[shocker]

I have panic stop before with them no lock up yet. The uplander rear disc are 12" compared to the fronts 10.25

[Old Gold]

Great write-up Shocker! I just came across this, even though it's been posted for over a year, and really appreciate the good photos and info!

Quick question: I know there was talk in the past of the '05 U-van rear caliper brackets being spot-welded to the beam axle on the Uplander. Was this the case, or were the rear caliper brackets simply bolted onto the beam axle (requiring just unbolting them from the donor car)?

Thanks in advance and I'm definetly curious about an update on how these have been working for you.

[shocker]

Yes the bracket is spot welded to axle.

[Old Gold]

Yes the bracket is spot welded to axle.

Thanks Shocker, much appreciated! Are the spot-welds pretty easy to get to and drill out at the wrecking yard? Is it something I could do with my cordless drill and the right bits?

Also, for those worried about brake-bias and having too much braking force in the rear (which sounds like it's not an issue for Shocker), an adjustable proportioning valve can be installed, inline, in the brake system without a ton of work, usually while on the car, with a tubing cutter and flaring tool. I haven't installed one on an GM FWD A-body, but have put one on a B-body, 1966 Plymouth Satellite with front Wilwood Dynalite disk brakes (4-piston calipers) and rebuilt rear drums (with grippy pad compound). It worked a treat and we were really able to dial in the rear. I mounted it under the car, but if you want to get fancy, you can mount them in the engine compartment or inside the car if you want instant adjustment. They usually sell for about $40:



It would probably be slightly more complicated to do this on an FWD A-body, but it's possible