My 2003 regular cab long be 4X4 base model 4.8 Silverado has a sticky rear caliper piston at 45K miles. The system has thinner rotors and single piston calipers that comes on non limited slip axles. Thinking about replacing system with the two piston calipers and thicker rotors that come on limited slip axles. It seems it is a bolt on swap requiring new caliper brackets, calipers, pads and rotors. Due to stuck caliper and parts needed to repair system, it'd be a good time to do it if it is indeed a worthwhile upgrade.

I've heard suggestions researching that maybe the master cylinder and proportioning valve are different and may not function properly with these parts from the old system. It may be that ABS takes care of this and the original parts work just fine. Know if this swap is a simple, straightforward, and worthwhile as it seems?

I have worked on many of these trucks but have never considered this aspect. I'm fairly certain the dual-piston caliper bracket has a different hole spacing (wider) than the single. If so, it won't bolt up to the backing plate bracket. Maybe you could try going to a parts store and comparing them. In fact, I can't recall seeing dual-piston rear calipers on a 1500 ("half-ton"), period.

quote:

Originally posted by egregore:
I have worked on many of these trucks but have never considered this aspect. I'm fairly certain the dual-piston caliper bracket has a different hole spacing (wider) than the single. If so, it won't bolt up to the backing plate bracket. Maybe you could try going to a parts store and comparing them. In fact, I can't recall seeing dual-piston rear calipers on a 1500 ("half-ton"), period.

Possibly the dual piston setups are common on Suburbans, but if you look at parts lists on rockauto, lots of dual piston options on 1500 pickups.

I wouldn’t do it since most of your braking is done in the front anyways. It could possibly make it easier to lock the rear brakes and activate the rear ABS.

quote:

Originally posted by PowerSurge:
I wouldn’t do it since most of your braking is done in the front anyways. It could possibly make it easier to lock the rear brakes and activate the rear ABS.

Either system can lock the wheels and activate the ABS, the two piston caliper system has more braking force before a lockup and better dissipate heat such as when loaded or towing. It possibly requires less pedal pressure during every stop since the pads are much larger.

It's 17yrs old & only has 45k miles on on the back of a pickup - how much braking do you really need to do? Much easier to swap a caliper & you're not really gaining that much utility for the amount of $$$ & trouble.

Be happy, my 2005 4x4 had drums on the back - had I checked, I'd have bought something else. BUT, I sold it in 2015 with 200k on the clock & the shoes were still plenty thick, because the adjusters froze after about 25k.....

If you're hell bent on doing it, make sure the parking brake is the same setup. I had a S10 with drums that I put camaro disks on & my college budget ran out before figuring out the right way to re-engineer the parking brake. Zip ties worked for about 1.5-2yrs before they broke -drove it for 3 years like that...

Sounds like you already had it all figured out pbs. Good luck.

NOT a chance this makes any sense. none. Despite what pbslinger says it doesn't add any braking force. run away.

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Originally posted by hrcjon:
NOT a chance this makes any sense. none. Despite what pbslinger says it doesn't add any braking force. run away.

This. The SUV's have a lot more weight over the rear axel than your pickup truck does (unless the bed is loaded or you're towing something with a good tongue weight all of the time) so they can make use of the larger pads and calipers (necessary actually). On the Ford expeditions Ive had, the rear pads actually wear out quite a bit faster than the fronts.

On your pick up truck given the age and mileage I wouldn't try it as it might really upset the braking proportioning between front and rear.

Even if it did help some, I can't imagine the improvement will be significant, unless you're doing a whole new braking system all the way around. I don't see the benefit outweighing the hastle of trying to modify things to make the dual-piston calipers work. If they bolt right up to the brackets you already have, it might not hurt. Ultimately, I would not expend any extra time or money to make it happen.

quote:

Originally posted by pbslinger:
I've heard suggestions researching that maybe the master cylinder and proportioning valve are different...

This would be my guess. I found a OEM set of four piston calipers for my truck for almost nothing. The valve, master cylinder, and brake booster are all different for that setup. Not a total loss, now I have spares as my other truck has the four piston calipers anyway.

Check with your factory shop manual or refer to a part number index to see if your current setup is compatible with what you want to be the end result. The volume & pressure may be different and may lead to premature lockup and/or bias.

Looking on rockauto, it looks like the master cylinder and proportioning valve are the same for either the single piston or 2 piston systems.

I think your only issue is (potentially) the rear caliper brackets not being able to bolt to the differential. I had occasion to look at a 2003 Tahoe and that bracket looks pretty wide.

Here's a youtube video of a caliper swap like I'm considering. Appears pretty straight forward.

https://www.youtube.com/watch?v=X3q2CxoNS5o