Olds Bravada, GMC Jimmy, Chevy Blazer rear ends

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bucket

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Oh yeah, and since it has discs, it could be three different widths (2wd/4x4/ZR2) so you may want to verify what you have will fit or not. Id say there's a good chance that it will.
 

Catbox

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It was out of a 2001 S-10, I know it was because I pulled it out.
I just can't seem to find the photo of the truck.

From a web page that I used to know what to look for when I was doing the search in the junkyard:
"The 8.5″ axle was used on vehicles up to 1999. The 8.6″ was used on vehicles 1999 and up. Since 1999 was the transition year, some vehicles received the 8.5″ while others received the 8.6″. The easiest way to tell the difference is by looking at the brakes. All 8.6″ axles have disc brakes and 8.5″ have drums."

and it was a ZR2 truck.
 

bucket

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It was out of a 2001 S-10, I know it was because I pulled it out.
I just can't seem to find the photo of the truck.

From a web page that I used to know what to look for when I was doing the search in the junkyard:
"The 8.5″ axle was used on vehicles up to 1999. The 8.6″ was used on vehicles 1999 and up. Since 1999 was the transition year, some vehicles received the 8.5″ while others received the 8.6″. The easiest way to tell the difference is by looking at the brakes. All 8.6″ axles have disc brakes and 8.5″ have drums."

and it was a ZR2 truck.

I won't say that info is wrong, but I will say that is news to me. From what I recall, the pickups never got rear discs (although an axle swap is not uncommon). A buddy of mine even had a couple of the later ones. The 8.5 and the 8.6 are the same basic axle, I believe it's just the bearings that are different, essentially. Also, iirc the rear disc setup is exactly the same as what was used on the 7.5" (or 7 5/8's... whichever someone wants to call it) axle housings in the regular 4dr Blazers. Same bearing ends on the housing. There was a difference between 2wd and 4x4 though, one had staggered calipers and the other did not.... I think. It's been a while and I've forgotten a lot.

At any rate, a ZR2 axle is fairly wide. How does the wms-wms compare to your '54?
 

AuroraGirl

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It was out of a 2001 S-10, I know it was because I pulled it out.
I just can't seem to find the photo of the truck.

From a web page that I used to know what to look for when I was doing the search in the junkyard:
"The 8.5″ axle was used on vehicles up to 1999. The 8.6″ was used on vehicles 1999 and up. Since 1999 was the transition year, some vehicles received the 8.5″ while others received the 8.6″. The easiest way to tell the difference is by looking at the brakes. All 8.6″ axles have disc brakes and 8.5″ have drums."

and it was a ZR2 truck.
so i have a 8.6 because its a 1999 Im pretty sure (late year 1st gen bravada, pre face lift) and it clearl had disk (The axle has the parking brake brackets and no backing plates)
 

bucket

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so i have a 8.6 because its a 1999 Im pretty sure (late year 1st gen bravada, pre face lift) and it clearl had disk (The axle has the parking brake brackets and no backing plates)

Bravadas got the 7.5/7.6 differential. The only ones that got the bigger differential were ZR2's and 5-speed Blazers/Jimmys. The 5 speed was not available in 4 door rigs.
 

AuroraGirl

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Bravadas got the 7.5/7.6 differential. The only ones that got the bigger differential were ZR2's and 5-speed Blazers/Jimmys. The 5 speed was not available in 4 door rigs.
Oh darn, but yeah that makes sense. 8.6 is way too large for such a small pumpkin. I should go get that cover off lol
 

AuroraGirl

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Bravadas got the 7.5/7.6 differential. The only ones that got the bigger differential were ZR2's and 5-speed Blazers/Jimmys. The 5 speed was not available in 4 door rigs.
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AuroraGirl

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I got the bolts out by using a 12mm deep impact socket, and pounded on (didnt need a lot of force.. lol..) i was able to remove 2 bolts with a 6 point 1/2 socket of higher quality than the other day i tried.

CARNAGE.
 

bucket

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I got the bolts out by using a 12mm deep impact socket, and pounded on (didnt need a lot of force.. lol..) i was able to remove 2 bolts with a 6 point 1/2 socket of higher quality than the other day i tried.

CARNAGE.

Do my eyes deceive me, or is that a broken pinion lodged in there sideways?! Impressive!!!
 

AuroraGirl

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Do my eyes deceive me, or is that a broken pinion lodged in there sideways?! Impressive!!!
yes, it can jingle around in there, its what was locking the shafts from turning lol

Thoughts on failure? The failure to me seems to be loss of lubricant and extreme neglect , but maybe it was a g80 bombing? i think bravadas all had g80?
 

bucket

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yes, it can jingle around in there, its what was locking the shafts from turning lol

Thoughts on failure? The failure to me seems to be loss of lubricant and extreme neglect , but maybe it was a g80 bombing? i think bravadas all had g80?

I'll guess that the pinion bearing blew while the truck was at speed and the momentum of the truck did it's thing to the pinion that no longer wanted to turn. But that's just a guess.

Or it was extreme abuse, lol.
 

bucket

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Oh yeah, I don't think it had anything to do with the gov-loc.
 

Catbox

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Moved the weeds off of it.
The 8.6 I wanted because it has the correct bolt pattern.
But alas, now I read the giant calipers will interfere with my frame as my car is quite low.
All because I didn't want to have to rework the Ferd 8.8 that is somewhere else in the backyard.
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Odd to think I have 4 rear ends in the backyard along with tons of other stuff you would miss on a first pass as a visitor...
 

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