Hey guys,I have a 94 s10 Blazer 4x4,with a replacement rear end from a nearby auto salvage yard.After bolting it up and triple checking everything,I test drove it (I behaved myself) through town,then on the highway and back with no problems.Thinking it was all good,I took it back on the highway,but only got about 6 miles out,and the front bearings of this replacement blew out..smoke billowed,fluid went all over underneath..and,of course,my colorful collection of curse words erupted as I got a look at the damage.I managed to limp it back to town,and we've been stuck here for a few weeks because parts are either hard to find,unavailable,or they're just too expensive.I'm literally down to just a few bucks,and I think I found the parts I need on rockauto .com,but threatened with being towed,I've got one shot at getting the right parts.I just don't know the specifics..I've seen them listed as "pinion bearing/and race" but I'm only a mechanic by necessity..I know it's a 7.5 ring gear,and was told this is a limited slip diff,so what do I order seeing all the choices : pinion crush sleeve repair kits,outer bearing and race(outer as in towards the drive line,or towards the tire?) ..sorry for writing a book here,but I love this truck,and would seriously appreciate some helpful advice.Thank you.

 

Replacing pinion bearings is a fairly big job that isn't really a roadside repair. Does the salvage yard have any warranty on the rear end you bought? Maybe they can give you another.

BTW, the "outer" pinion bearing is the one by the yoke (driveshaft). It's the smaller of the two. If it's the only one that needs replacement, you can do it without pulling the whole rearend apart. But to do the inner one, you have to remove the differential, remove the pinion, and press off the bearing.

 

As far as the salvage yard,they usually allow a 90 day return for non-electrical components,as long as there's a receipt accompanying them..as my luck would have it,my copy is missing.They have a good reputation for taking care of customers even after the sale,so my fingers are crossed.As far as a "roadside" repairs,I realize there are more optimal locations,but my options are limited.I have, however,moved it to a neighborhood a few blocks from my original location and I'll deal with it.Thanks for the info on the bearings,Tom.I've removed the old seal,and from the view,it looks like it may be the only bearing damaged.That would be great,but I'm preparing for the worst.The companion flange looks cooked where the seal was,but looks operational.I'll be sure to clean it up before reassembly.This truck also has the issue with the front differential not engaging due to the vacuum lines and actuator being crap,so I'm very thankful that's already been covered here in Blazer Forum.Very thankful for this forum as well.You guys are awesome,and could very well have even saved lives by passing down your knowledge.Again,thank you.

 

Update:Rear diff outer pinion bearing is basically shrapnel,and the inner race is fused to the pinion shaft.I've made many improvised tools,and attempts to remove it,but no luck.I'll try to post a pic of it with this update.In other news,front diff is working now,so I at least have the option of driving it instead of pushing it (lmao it's a 1/2 ton..very heavy) if I need to move it thanks to the info here on blazerforum.comI contacted the owner of the yard who sold me the replacement axle assembly,and he's working with me on another replacement.He said if those bearings are shot,the rest of the internals are probably toast as well,and that I should just get a new diff,but I looked and haven't found any damage at all..only metal flakes on the magnet,not the gears.Question is,do I repair or replace?He wants another hundred bucks for labor to pull another one,and although they deliver locally,he said that's not an option..meaning I have to figure out a way there and back with it.I appreciate any advice you guys might have,and I'm extremely grateful for the knowledge I've found here.Thank you!

 

It will take a ring/pinion + both pinion bearings minimum to fix this rear if the housing is still good. You obviously don't know how to set up a rear end by your comments, so I would not recommend you try to patch this one. Just get another rear from the junk yard.

 

I agree with Les. You may not be able to see any damage, but all those shavings circulated through the gears and bearings for who knows how long. That thing is toast.

It looks like you drilled the inner bearing race in an attempt to pull it out. Just the fact that you were able to do that tells me that the bearing got WAY hot and lost its hardness. Chances are, the pinion did, too. To fix it right, you're going to be into it at least a few hundred dollars, without labor. You'd be bucks and hours ahead to replace the whole assembly. That CAN be done on the side of the road (or under a shade tree) in a couple of hours.

 

Agreed with the previous 2 posts.

Setting up that preload on that bearing can be a tricky task, especially on the side of the road. Set it up wrong, not only could you cook the new bearing, but destroy the ring and pinion gears in the process.

You would be much better off just swapping out the entire unit again.

 

I agree and have rented a car hauler to get it back home and have contacted my local wrecking yard and I will be replacing the rear end again.I'm also replacing the front end differential and some other things in the next few weeks.Thanks guys for taking the time to reply.I do appreciate the knowledge and any time I can pay it forward,I absolutely will.

 

I hope it all works out for you. Maybe take the cover off the "new" unit and inspect it carefully before installing it?

 

I will definitely do that.I did actually check this one at the yard before I loaded it up.Everything looked fine,but there wasn't any oil in it,and I guess that's a red flag.I thought they might have drained the old stuff because of some EPA regulations or something.Stranger things have happened.I'll be a lot more aware of what I'm seeing next time.Again,thanks guys for the advice,and I hope y'all stay safe.