Project MULE - Expedition build on a 1991 1500 4x4 Suburban


Won't know until I get this back together and get it on the road. but I don't expect to have it. I never had the pinion angle at anything excessive.


Looking at those pictures, i have to agree with chilli on this one. Those bearings looked fine, and if i had to bet the seals started leaking after the metal shavings started cutting the seals up.

I would check and see if either the axle shafts were bent or the axle housing it self was bent. That or the other option of just poor heat treating on the axle shafts or they got hot at one time and it softened the metal.

If you figure out what happened let us know.



The bearings looked fine but they were damn near locked up. I remember fighting with fluid when I rebuilt the axles. I got fluid in today and remembered. Last time it only took 1.5qts. Its a 2qt system. I got 2 qts in this time. When I picked up the axles from the PO the shafts had mileage on them and the surfaces looked great so it was something I did once they came into my hands.

I got 2qts in now and took it for a drive, nice and quiet. I will drain, refill (flushing last bit away) and pull the shafts after about 500 miles to check the bearings and bearing surface.

I'm fully willing to admit this may have been a user error on my part. Just cant quite exactly pin it down.


hmm, well seems like you have it figured out so thats a good thing, i hate worrying about parts failing, i blew my rear axle up the same way before, but it was a 14bff, had to get a new axle cause the bearings welded themselves to the hubs and axle spindle. Crappy part was that it was my bad, just a tiny bit too low of oil, although i did fill it to the fill hole, just didn't get it down to the ends, i overfill by just a tad now, no more issues.



Hey guys, Yeah Im still alive.

We got back from our Cross country trip last october and just got busy. so here are some updates.

I got back into Motorcycles so I have been riding my dual sport a lot lately. My wife got into it for the first time so we have been riding a lot. In fact I've got so far into the bikes that I am starting to offer parts for them. I also got some classic Honda ATVs and am doing a partial resurrection/restoration on an '85 HOnda 250SX 3 wheeler.

As I mentioned in a earlier post I have to fix the dual swing outs. Hoping to finally get to that next week.

The motor project is still on the table. The block and crank is all machined and in storage for now. I still have to acquire almost all the parts.

Never got to painting the Mule last winter. I hope to finally get to it this fall. Just hope the paint is still good.

I am no longer selling the cheap LED lights. I had too many issues and the company decided to handle all the problems by dropping all their dealers. I am now selling Rigids and have not had one come back yet. When I get around to it I am pulling all the lights off the Mule and changing over to Rigids.

I may have a line on a small bench top 1/2" tube bender. If I can nab that I can bend up a new roof rack and make it slimmer and more aerodynamic.

I got the new axles shafts in a while back and they are still working just fine which makes me suspect i did not have enough fluid in the diff. Typically you reach your correct amount of fluid when it spills out the drain hole. well I did that the first time then drove cross country and toasted the shafts. This time I measured out the amount needed and tilted the axle up on one end and fill it up. so far so good. The pinion is at the correct angle and not aiming straight so that was not a fill issue. A few of us suspect the Auburn is displacing the fluid a bit but even that seems odd. Either way it's working now.

As overkill awesome (and a bit novel) as the center control panel was I am going to cut back the amount of switches and add a few more USB charging parts and make most of that panel section a little "cubby hole" so there is a place to put all the camera gear and gopros and such to charge while on the road. On that subject the whole wiring and console project really paid off during our trip. really made things a lot easier.

The A/C is out in the Mule so thats another reason no trips this summer. We brokes records just last week. Fry an egg on concrete you say? There is a guy that posted a video of pan frying a steak on his driveway a couple days ago.

Another thing is a few months ago I quit my day job and took my business full time so thats added a challenge in life and has kept me busy.

The other thing that's been on our mind and is sucking up my research time is we are considering purchasing a Class C RV this winter.

So to recap
YES... I am still alive
Been busy
Still love my Mule!


Expedition Leader
I look forward to seeing more of your adventures when you get back on the road PMA! Happy travels, cheers Chilli....:wings:

Recommended books for Overlanding

Boost Creep

congrats on your decision to sell quality lights now. between several different vehicles i have 3 light bars and 3 sets of pods from rigid with the oldest bar being i think 4 years old with no issues so far. i've got a tube bender but you'd have to drive to MI to use it. lol


Expedition Leader
Hello PMA! You know this is the best site to post all your updates. None of all that high pressure junk and censureship that you find at that`other` site... Here are your true friends... :)


any update on this build.... love this

are you thinking of doing the roof rack/rear bumper or battery box/compressor mount as a kit?


I am going to throw this tidbit of info out there for everybody.
I always use felpro differential cover gaskets.
They have slits in the sides at the axle tube level to allow gear oil to drain onto the spinning axles and run out to the bearings.
You may have under filled the axle but in my experience, even though it was a 25% reduction in gear oil, properly lubed those bearings would have still lived.
If your cover is getting hot from low fluid it will burn the paint off, if the bearings go bad, it's usually the cover gasket not having the lube slits in them.

What other site are we referring to? A Chevy site in Colorado?