Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

IS there a way to remove the pinion pin locking bolt? With basic tools?

I blew the rear end on my 82 GMC Suburban, it has the 6.2 diesel and 3.73 gears… Looks like one of the spider gears on the pinion pin was locked up and caused them both to shatter… Not a good thing… Anyway, when trying to remove the pinion pin so I could replace that and the gears, the locking bolt broke and stopped me from pulling it out… is there a way to get it out so that I can replace the gears?? Without doing a ton of damage or having to buy any expensive tools?? I am dead broke…

You’re talking about the bolt that holds the pinion pin into the carrier? If that bolt head snapped off, then the only way to remove the bolt is to weld a nut thru the center of the nut back onto the bolt and hope this turns the bolt out. Otherwise, remove the diff so someone can attempt this or replace the diff.


You can’t pull the diff out without removing that pin… The axles won’t come loose so that you can remove those c-clamps.

Drilling the bolt out and retapping threads may be about the only other option short of replacing the entire axle.

What I would be concerned with is why the spider gear locked up. Lack of oil due to a leak? If so, what about the ring and pinion gears?

Actually, the oil was quite burned. The truck (SUV) has only about 445k miles on it. I did notive that there were some marks that showed that one of the spider gears had been locked up for some time…

Then you need a new diff.


At this point, the cheapest and easiest way to deal with this will be to replace the rear end. They’re easy to replace and a dime a dozen. I wouldn’t fight with it. Just throw another rear end under it. Junkyards are full of these trucks, so another one won’t be hard to find.

Count my vote as one to just replace the entire rear axle. Around here a complete axle like that goes for about 125 from the yards and with some digging on Craigslist you may find one for less than that.

Problem is, there aren’t that many of these Suburbans in junk yards in my area… I live in basically the middle of nowhere. I literally live in THE poorest county in the country… There just aren’t that many vehicles around.

If you check with a junk yard you might find that the axle interchanges with all the pickups of similar rating. And I have often bought them complete with springs, brake cables wheels and tires for less than the cost of the ring and pinion.

With a large hammer and punch you can drive the pinion shaft through, the lock bolt will shear off. That was a common problem encountered when replacing axle seals.

Rod Knox has the BEST solution…Replace the entire axle…

I would have to agree with all you said you need to replace the axle. If you just replace the spider gears,you will need to get them from a used axle anyway. So just get the whole axle. Setting up a axle with different dif with out the right tools and know how, will lead to more problems. Remember also to use new u-bolts to put the axle back on. The olds ones should never be reused.

At 450k miles plus and with badly burned oil I don’t see the point in installing new or even good used spider gears in a rear axle that is probably toasted beyond recognition.
I can only imagine what the pinion and carrier bearings are like along with wondering if this worn out rear axle is going to shuck an axle (C-clip type) if slopped back together.

I did inspect the rest, and there is no slack in the bearings, or in the pinion. The only damage was to the pinion pin and spider gears on the pin. Looks like it siezed just the one, and when it went the other one collapsed as well. I can tell you this, I also took the cover off of the front end to examine it and found no damage there. The gear oil in the front axle looked brand new still.

A reverse rotation drill bit has worked in all such situations for me. It would be worth a try.

If you try to repair this rear end it is going to howl like a banshee ! I had a friend who worked at a GM axle plant. His job was to repair differentials that came off the line noisy. They would give him one attempt to read the tooth pattern with Prussian blue and re-shim the rear end. If it was still noisy they would scrap it.

The problem with the howling is mainly noise right? The big thing is, I won’t be able to hear that over my engine. I have the 6.2 diesel and a pair of massive flomaster mufflers. I couldn’t hear the rear axle before it blew, although I guess it was howling then.

Do yourself a BIG favor…Find a used axle assembly with the correct gear ratio and install it…You will thank us all…

It seems experience is the best teacher, Caddyman. And it sounds like you have seen a few good plans turn to disasters also. I have drilled out broken spider pins and then found that both axle shafts were worn out and the pinion bearings shot. After all those miles it’s a wonder anything in that axle isn’t worn out. Wheel spin and poor lubrication will take the spiders out prematurely but regardless what wore out the spiders the metal that was cast off from the wear must be assumed to have damaged all moving parts in the Axle.