'05 Silverado: Change rear axle from drums to discs?

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The Artist formerly known as Turbo84
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My '05 Chevy pickup has apparently towed too many miles for its taste, and the rear end is starting to whine a bit. Rather than spending a lot of time rebuilding the present differential I was just going to try to find a complete low-mileage rear end to swap into truck. My truck has drums in the back, and all I'm finding on the net so far is a large supply of '06 and later rear ends that are equipped with discs. So I've got the choice of swapping the drums onto the "new" rear end (assuming there's nothing odd/welded on the new axle tubes for the caliper brackets), or keeping the discs on the replacement rear end. What I don't know is if there's a residual pressure valve in the rear brake circuit of the truck (striking out so far on the web) which may cause issues with the calipers. Anybody have any insight into the brake system of my truck?
I don't mind spending time modifying/updating the Corvette, but I'd rather not have to burn up a bunch of time trying to get the pickup repaired and back on the road.
Any helpful input is appreciated.
 
Mike, Here is a guy that swapped a 2004 disc brake rear into a 2005 drum rear axle. The post is from 2007 so he who knows if the later fits. There is some discussion that the 2005 went to drums because of warranty issues and then changed back to disc in 2006?

http://www.fullsizechevy.com/forum/...75976-2005-2006-silverado-rear-disc-swap.html

Thanks Larry.
Regarding the warranty issues, I had a bad experience with the discs on the '99 GMC I had before the Silverado. The rotors warped big time by 30k miles, and got turned on warranty. Needless to say they warped again quickly, and I bought new (aftermarket) rotors for it at 40k miles.
I read the thread at that link. While reading it I was pretty happy that he didn't mention any issues with a (possibly installed) residual pressure valve in the rear brake circuit. I then saw that a poster (five years later) asked about the RPV issue, but apparently the OP never saw the updated thread question. So, I'm still a bit unclear if there is an RPV in the system.
I think I'll still try to find a low mileage rear end, most probably with discs, and then keep asking questions with whomever I can, to hopefully eventually get a definitive answer on this. The second best option is to install a rear disc brake axle setup on the truck, and then get it drivable. I've got a few pressure gauges laying around that I could plumb one into the rear flexline area to measure the residual pressure. Minimal pressure, I'm home free. A couple pounds, and I'll just have to talk myself into swapping over the backing plates and drums from the original axle housing onto the new rear end.

Thanks again.
 
Don't know if this is helpful or not but my '05 Suburban came with disc brakes in the rear (5.3L Flex-fuel, LT, 4x4 but not Z71).

DC
 
Don't know if this is helpful or not but my '05 Suburban came with disc brakes in the rear (5.3L Flex-fuel, LT, 4x4 but not Z71).

DC

That's what's got me so confused on this deal. I haven't quite figured out why was only some of the light truck production limited to drum brakes, while others had discs. I had hoped that Chevy commonized the master cylinders and ABS units for light trucks, but I looked at the Rock Auto site and there's different replacement part numbers for these items depending on whether the vehicle has discs or drums.

Given that I can't make sense out of Chevy's parts combinations on these trucks, I'm slowly leaning toward getting the later low mileage axle assembly (w/discs) and then transplanting the current backing plates and drums onto it.
 
Back on the road.

Well, after several dead ends trying to find out a bunch of details regarding the differences between disc and drum equipped trucks, I finally lucked out. I found (on ebay) a low mileage rear end (w/10 miles!) out of a dealer lot damaged '06 GMC. Very fair price with free shipping. After it arrived I took the rear cover and drums off and looked everything over. The brakes looked new (as they should be), and the internal differential area was damn clean. I was happy to see that.

Swapping out the old axle assembly and putting in the new one was amazingly quick and simple. I'm so damn used to installing non-stock type stuff on the Corvettes (that always seem to need modifications to fit), that it was a nice change of pace to be able to just hook up the pneumatic gun and run most of the bolts off in a quick burst. The hardest part was just trying to figure out where to disconnect the brake lines to minimize the headache if a rusty line twisted off. I was fortunate as it seems the two month exercise of spraying penetrating oil on all the bolts and fittings during the parts search paid off. Without the rear axle howl now, the truck is as quiet as it was when it was new. I was worried about not having a tow rig for this summer, but fortunately I'm back in business again.
 
Frozen brake/hydraulic lines.....

I got pissed one day over that crap, left the line in the 'loose' position but very slightly twisted....

took my air chisel to the bolt what was still in the casting/fitting...and shot maybe 3 shots to it, not enough to destroy it, but enough to rattle it's teeth a bit.....works like a charm......kind of like handling a air gun on a wheel nut, you know when to quit, because it's your gun....

not to get all touchy feely over it ......


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