My truck went back to the dealer for the THIRD time for front diff problems.

FIRST time was just a simple leaky pinion seal fix
https://www.dieseltruckresource.com/...d.php?t=165868

SECOND time, they didn't properly torque the pinion nut, so the entire diff grenaded itself. So, they rebuild the entire diff.
https://www.dieseltruckresource.com/...d.php?t=165855

THIRD time, I get a horrible clunking sound after shifting from 4WD back to 2WD. It sounds and feels like I ran over a boulder or the front of the truck just fell out the bottom. So they tell me that the pin (I'm assuming this is the pinion pin in the differential housing that holds the spider gears in) came loose and chewed everything up. I guess that means the clunk was the pin contacting the main pinion gear? Anyway, so now they're rebuiliding my differential again!

In retrospect maybe I should have just put up with the leaky pinion seal. It would have saved me a bunch of trouble. I sure hope this time the problems are resolved once and for all. I really wish they'd just swap out the whole front axle assembly for a new factory-built unit but they tell me they can't do that. So my truck is at the mercy of their ability to properly rebuild it, again.

 

I say if it comes apart again try to sit the service manager down and demand a complete replacement of the front differential since his techs are not skilled enough to fix the problem the first time.

 

Yeah I will. I was pretty close to calling DC Warranty this time and if it wasn't for them being very polite, responsive, apologetic to me, I would have. I just hope either this solves the problem once and for all and if not, it better blow up within 12,000 miles while it's still under warranty. I will probably test the 4WD frequently once I get it back. If it fails again though, it's probably going to another dealer at that point.

 

Mine leaks a little, if I put the hub kit on it won't move much and might not leak. I have a $100 deductable on the warranty so if I don't have to replace it, it's like 100 off the hub kit price. Does dino oil leak less than syn in the front diff. Probably don't need syn up front.

 

If anybody in the San Diego area needs a good independent diff. guy,p.m. me for info. I don't think we're suppose to advertise here.

 

Oh boy. I hope that doesn't happen to me. Mine is in the shop now getting new differential bearings (pinion, carrier).

 

I got a leaky front pinion seal right now. I have held off gettin it fixed, I guess I'm gonna hold off a little while longer. Keep us updated.

 

Well the dealer called and my truck is apparently fixed (again) with another diff rebuild. They diagnosis they gave me was that the main shaft/pin that holds the spider gears in place was knocked loose and was contacting the main pinion gear. They said there's a small retaining screw that's supposed to hold this shaft in place and it had worked loose, allowing the shaft to slide out. That retaining screw is supposed to be LocTite'd in on the replacement part when it arrives at the dealer I guess, and it wasn't, so this time they ensured it was LocTite'd in place. We'll see how it holds up this time.

 

sounds to me like incopetance and lack of detail in the work.

99% of the time both failures you've reported are ether due to not aplying locktight, or from not cleaning the oil off before locktighting...

just think all this to save the $0.02 worth of locktight and 2-3 min at the dealorship on the job by the tech.

 

FYI - you can't order a complete housing from AAM.
They only sell them bare, and you have to put them together.
If it fails again, just take it to a tranny shop that does a lot of gears and bill the dealer.

 

Yep, I think you're right. Unfortunately, I don't think the dealer suffers the consequences and learns from their mistakes because DC warranty foots the bill for the screw-ups. It looks like they blamed it on "bad parts" so they could submit subsequent warranty claims to DC.

 

That's good to know. I didn't realize it wasn't available as a complete assembly.