Lost my rear end.

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Pmcb

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Pat
Truck Year
1987
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GMC Sierra Classic 1500
Engine Size
5.7
My rear end gave out last Saturday, driveshaft and wheel slammed my door and went down the road. Now I am having trouble finding a rear end. 1987 GMC Sierra Classic, 4x4, Auto, 5.7l, 3.42 gears.
What other options are there? A complete rebuild might be out of my league. Thisn is a daily driver , not offRoad rig.
 

PrairieDrifter

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You mean axle shaft and wheel? Take it to someone who can rebuild it, will probably be 1500-2000 depending. Or if you're capable of an axle swap then do that, finding 3.42's will be a challenge.
 

Ricko1966

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Just keep looking for used. Also try car-part.com if you haven't already. It's a fantastic resource for finding parts at local yards.
You know that 72 8.5 10 bolt a body rearend they never made? That's where I found multiple. I pi$$ everyone off when I say it's easy,but new bearings and seals in a diff is NBD. Guess I need to remember we all have different skill sets and aptitudes. But it's easy! HaHaHaHa!
 

Pmcb

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I can find several rear ends that figments say are for 1988 GMC Sierra 1500, but online they all say will not fit 1987. What is the difference? Wheel base? They are same gearing 3.42.
 

legopnuematic

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88+ GMT400 rears are not a direct swap, with cutting off and welding new spring perches and shock mounts they will. That’s a pretty big project, along with that the 2wd 400 rear ends are about 2” narrower than a squarebody rear, and the 4wd 400 rears are about 1” wider than a squarebody rear.

Now a 5 lug 10 bolt (or a 12 bolt) from a C10 will be a direct swap, with the exception of having to change the axle shafts to 6 lug shafts. Changing axles is not very difficult provided the cross pin bolt in the carrier comes out and isn’t broken.

Remove cross pin bolt, remove cross pin, push one shaft in, remove c clip, push other shaft in, remove c clip. I’d recommend changing wheel seals at a minimum and maybe outer bearings (not much $$ to do it), install new shafts and reverse disassembly.
 

SquareRoot

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Carnage? Where's the pics?
 

Pmcb

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the two things that make me hesitant to rebuild: is there damage to housing, and shimming to get things within thousands. How hard is it really to rebuild? I will be pulling the rear end off tonight so I should be able to see any obvious damage to housing.
 

TotalyHucked

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Here in the SE, it's hard to find axles for these trucks these days. I'd be surprised if there's such bad damage the axle can't be rebuilt. Once you take it out and inspect, you'll know better obviously. But if at all possible, I'd just get that one rebuilt. If you don't feel comfortable doing it, you could easily drop it at a shop to be done. That's what I did. I could've done it myself and could've spent the $500 labor charge on the proper tools, but since I'd never done one, I didn't want to take a chance and chose to have a pro do it.
 

Ricko1966

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New bearings use your original shims,shims are made for housing variances as long as you are using your original housing,carrier,ring and pinion. No shimming required. As for damage in the housing I d need to see it. You are going to need a press and a bearing separator, to pull diff bearings and pinion bearing, other than that it's ordinary hand tools. You may need a case spreader,maybe, nbd you can make on if you have to.
 

RustyPile

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Now hold on a minute!!!! You guys are talking a complete replacement or rebuild.. My money is on a worn out "C" clip, or the end of the axle broke off at the "C" clip groove and walked out of the housing.. Worst case scenario, you damaged the housing in the axle bearing area, but more than likely all you'll need is a simple axle and axle bearing replacement.. Aftermarket axle manufacturers are all over the internet.. Moser, Strange, just to name a couple.... Post pictures of the end of the axle..
 

RetroC10Sport

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Just keep looking for used. Also try car-part.com if you haven't already. It's a fantastic resource for finding parts at local yards.
It is, except when you work with idiots. I can't tell you how many listings I've had to change on there because the ********* think a hood for an '04 Tahoe fits a '16 Civic. And I was thrown under the bus because I was the new guy when my accounts there got fuggered up. Long story.
 

Pmcb

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GMC Sierra Classic 1500
Engine Size
5.7
The differential is completely trashed, the pinion gear is badly damaged, so I would need a complete rebuild. Axle shaft ends got tore up from bouncing down the road. Bearing will not be a problem, I just wonder about the pinion gear, and I will have to look to see if I can find the shims in the mangle mess that poured out. I would enjoy trying to rebuild but it is daunting.
 

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