Using '94+ rear brake calipers in '93 and earlier vehicles

[Regal]

I've been putting off doing a job where I need to remove the rear calipers for a while, since I'm not sure they're going to go back on.

I have been considering replacing them with '94+ rear calipers though I've been told the parking brake setup won't be compatible.

What I want to know is if there is any possible modification that can be made to make the parking brake work on '94+ rear calipers in a '93 and earlier car? Currently the parking brake is not even hooked up and needs new cables I guess but ideally I want it to work.

[pwmin]

I was able to make them work on my 91, but I don't remember exactly how I did it.  I think it involved swapping the e brake pedal, some cables and some modifications to the brackets on the calipers.

[Regal]

Thanks, I'll either just replace them with factory setup or maybe go with a '94+ caliper and worry about the parking brake later.

Is there any better performance with the later caliper in regular braking or is the reason for going with the newer design mostly for better part reliability during maintenance?

[pwmin]

I don't think it's much of a performance benefit, more the caliper design

[White93z34]

I did the 94 swap on my cars 100% for the sake of reliability, nothing else.

the rear cables are different, but the front one still works as does the pedal

the rub is there is a bracket spot welded to the rear frame rail, drivers side that needs to be drilled out and swapped with one from a donor car. I wanna say I just used self tapping sheet metal screws to put the new bracket on my car, not ideal and one of these days I should go back and weld it on now that I have the ability but its been holding up fine since I did the swap in 2008 or 2009

[Schurkey]

The first-gen rear calipers get a lot of negative feedback on various forums.

My two vehicles ('92, '93) have had ZERO problems with the rear calipers.  They're easy to service, they do not need "special tools" to "wind the piston back in".  I replaced the rear calipers (using stock-replacement "rebuilt" calipers) on one vehicle because of all the bad publicity; but nothing changed.

Swapping to the later calipers is a lot of work for no benefit.  It's possible for calipers to become seized or "sticky"; aluminum calipers are worse in that regard than iron calipers.  So, sure, you might need to rebuild or replace calipers that have an actual fault.  Merely swapping good "first gen" calipers in proper working condition for good "second gen" calipers in proper working condition is not really an upgrade in my opinion; and if you're giving up the park brake, it's a downgrade.  And probably illegal, too.

If you're having problems with poor braking power, and a hard pedal...you probably need to replace the booster not the calipers, and properly bleed (flush) the hydraulic system.

Edited October 24, 2022 by Schurkey

[Regal]

The brakes are "fine" but when I did the brakes last I put an excellent kit in the front and just some cheap new old stock metallic pads in the back with the existing rotors that at the very least should have been turned.

The "excellent" pads in the front wore out pretty quick when I had a faulty alternator causing the car to almost drive in a limp mode and I have had to be replace the front pads prematurely and may have to again already. I think the thousands of miles put on the car (no choice) while I had the alternator issue I was trying to chase down before realizing what it really was also put extra strain on the rear brakes and I have new ones on hand anyways but really need to get back there to replace the rear bearing/hubs.

Since I'll be back there, of course I want to put in the rear brake parts I have on hand (and am not sure the '93 pads would fit into the '94 caliper anyhow). The last time I took apart the rear calipers, one of the pistons popped out of the caliper and there was no way it was going back in.

For retraction, does one of the rear caliper's pistons need to be turned counterclockwise while the other needs to be turned clockwise? That's how I wonder if I screwed up.

[rich_e777]

IIRC its the same for both sides, I use a combo wrench with a screwdriver in the boxed end to use to turn the piston back in. No need for a special tool. Clockwise should be threading the piston in

[Schurkey]

First Gen rear calipers:

DO NOT  "turn the piston" to wind them back in.  This is possible, but it's a waste of effort, and a waste of time.

REMOVE the park brake lever (one nut, and washer)  Push the piston STRAIGHT IN, (I use a vice-grip C-clamp) the threaded rod spins instead of the piston.  Re-connect park brake lever once the piston is retracted.

Don't forget to reset the park brake by applying it several times after the rear brakes are reassembled.

[rich_e777]

We may be arguing green apples to red apples here. The rear calipers on my 1994 and 1995 Cutlass were damn near effortless to turn back in with the method I described and would NOT have turned on their own when applying pressure with a c-clamp like the front calipers. 

Edited October 25, 2022 by rich_e777

[White93z34]

On 10/24/2022 at 10:37 AM, Schurkey said:

Swapping to the later calipers is a lot of work for no benefit. 

I couldn't disagree more. 

I don't know what area of the country/world you hail from but back when I was daily driving a w car in the rust belt, it was a yearly affair that something would go wrong and ruin a set of rear brakes, be it the caliper failing to release or most commonly the slide pins managing to get absolutely seized in the caliper housing. I went round and round with this, through way too many sets of rear calipers.

Since I swapped to them I've had to replace one caliper that did fail and the setup I put on was just yanked off some random Cutlass and slapped on my car. Again this was not done for any sort of performance issue despite them being slightly bigger, it was done out of the quest for brakes that don't need attention yearly.

I'm glad you haven't had the absolute hell of dealing with these cursed brakes but man they drove me and many others to the brink of insanity. I'd imagine they changed them up for a good reason.

 

[55trucker]

If one updates the older caliper to the newer design one must also make use of the later rotor for the 94+ caliper. One cannot mix & match *old* with *new*.

[55trucker]

On 10/23/2022 at 10:16 PM, pwmin said:

I don't think it's much of a performance benefit, more the caliper design

Actually there is a mild improvement, the earlier rotors are 10" dia, the later rotors are 11" dia., the pistons in both early & later calipers are the same dia. so the force is the same but that 1" dia. difference in the larger rotor provides more braking force than the smaller rotor will provide.

Edited October 26, 2022 by 55trucker

[GTP091]

I did this swap myself and am very happy with it. The 91-93 sliders are a horrid design.  Even with the later aluminum slider they seize up.  I got my donor parts off a 96 regal and rebuilt the callipers and powder coated them.  I bought new rear cables for a 96 as well and used a female threaded coupler to tie the equalizer and right rear cable together.  I can’t remember exactly but part #9 was different between the years.  To make it work I cut the threaded rod coming out of part #9 in the photo and screwed the coupler onto it and then screwed the right rear cable rod into the other end of the coupler. The coupler is right at the #8 spot in the photo.  

Works great.

You’ll need to replace the callipers, rotors, calliper brackets, get new rear park brake cables, left and right from a 94-96.  very easy swap.

 

 

Edited October 31, 2022 by GTP091

[pwmin]

found my old thread.  stupid photobucket