Finally decided to join up after browsing this site for months...... anyway. Driving the other day had an odd vibration out of no where. Pulled over to check the usual stuff....all good. Went to merge back onto the highway at a low speed then ...bam. Thought it was just a bearing but turns out I snapped the pinion shaft.....no clue how.

It's a 9.25" with 3.55's and the factory LSD. Anyone ever hear of the shaft snapping in these things?

The picture is what it looks like since I pulled it last night.

 

I feel your pain...My rearend went out at 70,000 miles, had it completly redone, 1800 dollars i think, somewhere in that ball park. right now its at 129,000. I just blew the rearend out of it yet again. Its at the shop getting an estimate on it but this time I think I will be getting rid of it. Anyhow, im not to impressed with the rearends in these trucks.

 

Well if you're getting rid of yours wanna swap wheels/tires?? ha.....the worst part is mine is right at 49k miles. These rears seem to be a horribly weak link

 

Ouch!!!.
First for me in seeing pictures of it.

 

Yikes! Sorry to hear about that. At least it's a reason to upgrade to lower gears. If you decide not to upgrade, I have 3.55s for sale in the classifieds.

 

hmmm. never really had any issues with my rearend and its at 145K, besides my shaft breaking off, but than again i had to much weight and it was on 4x4.

 

The AAM 9.25" is actually a pretty solid axle, and is actually a bit stouter than both GM and Ford 1/2 ton offerings.
It's the factory LSD that's a POS and once those clips break off, it's just a matter of time until they work their way into the ring/pinion and anywhere else they can chew things up.

ANYONE who buys one of these trucks with the factory LSD in it who doesn't have it yanked out of there will eventually see a rear end failure. PERIOD!!! Mine came out at 19k miles in favor of an Auburn Gear LSD, before it had a chance to do any damage.

There is SO much on forums, Google, etc. about how bad these things are, that there is NO excuse for anyone leaving it in there. The '06+ trucks do seem to have a bit better clips, but you still hear of a failed LSD once in a while with newer trucks as well.

 

Same. Been through 2 gear swaps (4.10's now 4.88's) and still have the oem LSD and the rear is still running good at 114k. Also lost my drive shaft late last year due to incorrect pinion angle. Got a used one from a salvage yard and its been running good ever since.

After those pics though i may consider removing clips or going with aftermarket.

 

You may find you don't have the clips in place any longer after 114k miles. Some get lucky and have them break off pretty much in one piece and get to the magnet after only causing minimal and inconsequential damage...

Pyro (former site moderator here) had made it to 104k miles on original LSD, then his ring/pinion started screaming like death. He made it from Orlando to my 4x4 shop here and they got it on the lift. Tech said if he had to go another 30 miles, the rear end wouldn't have made it. The clips gouged the sh*t out of everything...