Hey guys I have a 2004 H2 Hummer, I own a cabin in KY. Some friends of mine recently bought an 8000lb camper, I was obliged to tow the camper up to the top of the hill for them. in one area it's a 40% grade. This should really prove to be a good test for the Hummer I thought. I have 13.5x37" tires on it and they never broke lose once. I was proud!

200 miles and two weeks later I'm driving down the highway and the three big chucks of the front differential housing cam off. Called for a tow truck and strait to the nearest dealership it went. I also found out the top 180 degrees of the transfer case was cracked and had been welded buy the previous owner. How nice! I had them both replaced for actually what I thought to be a good price $4800.

Here's the question..

Could the front differential have gone bad from towing the camper up that steep of grade with my over sized tires and the exceeded weight of the camper.

Truck has 144,000 miles and obviously not well taken care of since the welding job on the transfer case says a lot.

Truck sure looks pretty, isn't that what really matters.. Haha

 

I'm sure towing that load uphill was probably what made the front diff fail but with those miles it could have been a coincidence. $4800 is a chunk of $ but your truck looks great and it is worth it.

 

Thanks Phil I appreciate the compliment! I guess I'll never really know for sure. Someone sure must've towed something pretty heavy to crack that transfer case the way it was. I have attached a picture of it.

 

If the Diff was already damaged as the op said then any towing will make it fail but towing 8000 pnds isnt a big deal if everything is in perfect cond .

@chief was the repair made by a dealer ?. What fluid did they used . New or rebuilt?
Was it making any noise before failing

 

The 200 miles I drove after towing the camper the Hummer drove good as it should. I never heard any noise it just all of a sudden broke going 70 down the highway, after that there were very loud clunking sounds and I knew right away it was something serious. This was when the front differential broke.

The work was done by a Chevy dealer and they couldn't find a new front differential so I found a remanufactured one on eBay and had it sent to the dealer.

While changing the differential they discovered the transfer case crack/weld and replaced it with a new one. I don't know what kind of oil was used.

I read somewhere the truck was designed to pull 6700 lbs. but not a credible source. Good to know that 8000lbs wouldn't normally be a problem.

 

6700 is right ... You can pull up to 8000 in a emergency but not recommended . And in my case I tow mostly flat (florida)
I wouldnt pull 8000 very often

Im having a whining noise when truck needs to put some torque to going on a hill . Crossing fingers is not the differential or TC .
2 days ago the 4x4 low got stuck and a 4wd service showed . All cleared when turn it off and on again
I just checked the fluid and seems good .
Will replace fluid tomorrow to check for any problem just in case

 

I could still use 4H and 4L after the front DIF broke just couldn't move the truck without loud banging noises.. Haha

How did it go after changing the fluid?