Here's my busted Differential pictures...

[Mike E]

For those of you that are interested in what a differential looks like when it fails...

[mancilg]

looks like someone shot it

[DRTYFN]

It's like a little toy differential.;):D

[rkcrawl]

No internal shots? Bummer.

[HummerNewbie]

That would explain the leaking fluids :mad:

[Mike E]

No internal. If i was there i would open it up but I had to rely on the service guy to take the pics.

[HummBebe]

No internal. If i was there i would open it up but I had to rely on the service guy to take the pics.

It might have looked like this :D

http://i12.photobucket.com/albums/a240/HummBeeBe/Carnage.jpg

[deserth3]

I'd be interested to see the inside.

[ketcat]

This question may have been answered in the past but.....

Is the front diff on the H3 an AAM 725? 185mm (7.28") ring gear.

Is the rear an AAM 800 or AAM 860? 205mm (8.07")or 220mm (8.66")ring gear.

[f5fstop]

This question may have been answered in the past but.....

Is the front diff on the H3 an AAM 725? 185mm (7.28") ring gear. Yes

Is the rear an AAM 800 or AAM 860? 205mm (8.07")or 220mm (8.66")ring gear. I believe it is the 860

[f5fstop]

For those of you that are interested in what a differential looks like when it fails...

Couldn't they patch the hole?:D Yes, that is one destroyed axle.
GM may have requested it be returned un-opened for inspection; I would if it was my part.

[ketcat]

I believe it is the 860

Thanks for the help.

[rkcrawl]

It might have looked like this :D

http://i12.photobucket.com/albums/a240/HummBeeBe/Carnage.jpg

I know, thats why I was curious, to see if it was the same issue with multiple teeth broken off. Sound like in this case one of the tooth chips probably got bound beteen the pinion and a good tooth on the ring gear causing a boom with enough force to send it out through the housing.

I hate for people to be experiencing this and really hope its a problem thats been identified and fixed already. If not, there is gonna be a lot of these from people who wheel them.

[NEOCON1]

some gold bond for bebe's teeth and some chewing gum for mike's hole :D hell those are both easy to fix on the trail :eek: ;) :D

[usetosellhummer]

That's bad but in Durango at a Hummer event I was helping with tech support when we saw a guy in an H2 over rev and raise the front a foot in the air. She came back down spinning and the front diff cracked open from the center like an egg. We had to flatbed it in and they actually covered it at the Gm trailer at no charge to the dude.

[f5fstop]

some gold bond for bebe's teeth and some chewing gum for mike's hole :D hell those are both easy to fix on the trail :eek: ;) :Dhttp://hometown.aol.com/f5fstop01/images/rollingonfloorlaughing.gif

[Hummie2]

That's bad but in Durango at a Hummer event I was helping with tech support when we saw a guy in an H2 over rev and raise the front a foot in the air. She came back down spinning and the front diff cracked open from the center like an egg. We had to flatbed it in and they actually covered it at the Gm trailer at no charge to the dude.

yep, that is one of the weak areas in the H2 also. I have see a few H2 open up like a cracked egg. Usually they are spinning and suddenly catch traction when they crack from the sudden shock load to the axle. I don't believe these H3s were spinning or broke traction at the time they broke the gears.

Those look like cast aluminum bearing caps in the picture. The caps will let things move when the strain becomes high enough. Definitely some room for improvement.

GM should cover things if they happen @ a sponsored event or Hummer Happening. Those are supposed to be controlled situations. Dealers are required to do two off-road events per year and damage to the truck there should be warrantied. I have seen one of our local dealers give a demo to customer and flatbed a broken rig back to the shop for warranty repairs more than once at Hummer Happenings. That is what customer satisfaction is all about and that customer will remember next time they are looking for a new Hummer.

[f5fstop]

GM should cover this under any circumstances, not just at a Hummer Happening. So far, I believe all have been covered under warranty at the dealers.

[Hummie2]

GM should cover this under any circumstances, not just at a Hummer Happening. So far, I believe all have been covered under warranty at the dealers.

Yes they should. Hopefully we won't hear the "THATS OFF-ROAD DAMAGE" bs that came up with the H2s.:mad:

[f5fstop]

Component failure is one thing; however, I can see if the case, trans or engine are dragged and pans ripped open not being covered.

[HummBebe]

Usually they are spinning and suddenly catch traction when they crack from the sudden shock load to the axle.

OK, let me ask you this...
the "Electronic Traction Control" is different than "Stabilitrac". That being said, should not the ETC stop the spinning, therefore preventing the axels from being damaged.

I admit I do not understand the minutia of how these two systems work, but I was under the impression that we were to let our tires spin so that the ETC would activate and apply the traction to the wheels that had it??

I also understand that different terrains require entirely different techniques. So some clarification would be helpful I think, to all.:D

[Hummie2]

Yes,trac control does require wheel spin for it to work. A spinning wheel that suddenly catches traction sends a high shockload to the drivetrain however and thats a shortcut to disaster for these rigs.

Trac control works pretty well, but it won't eliminate all wheel spin. There is a reacation time for it to sense wheel spin and its pretty easy to over power it altogather. I have a front locker in my H2 and very rarely use it because trac control does a pretty job all by itself if given a chance to work. The H3 trac control appears to work as well or better than the H2s, but I think from watching a few H3s they might have a higher RPM threshold for it to sense wheel spin(?).

I still hold my breath everytime I see one spin:eek: and I long for the old days when I used to be able to blast through things with all 4 wheels spinning sending mud, pinecones, and bolders flying 100' in the air.:D

BTW, Bebe check your PM. I finally noticed the question you asked.

[HummBebe]

Thanks Hummie2!

I was at a Hummer Happening last weekend, put on by Rod Hall. We were at the trials course, where we were purposely put into a difficult traction situation where we had only two wheels with traction. Passenger front and Driver rear.

We were told to spin the wheels until the traction control came on and pulled us up. It was so scary, especially after what I had just been through.

It was VERY difficult for me to do. I wanted so bad to BTM my way through the obstacle. But sure enough it worked. It took a little bit longer than I would have liked for it to engage. It did, and I cleared the obstacle.

So, it think in soft dirt or loose gravel/rock it is an invaluable system. On slickrock, which grips like sandpaper, any kind of spin is a diff killer:D

[NEOCON1]

I still hold my breath everytime I see one spin:eek: and I long for the old days when I used to be able to blast through things with all 4 wheels spinning sending mud, pinecones, and bolders flying 100' in the air.:D




X 2

i had a 76 K5 blazer fulltime 4X that was 20 years ago and i couldant break it , i tried pretty hard too :D oh the gold old days ;)

[NEOCON1]

Thanks Hummie2!

I was at a Hummer Happening last weekend, put on by Rod Hall. We were at the trials course, where we were purposely put into a difficult traction situation where we had only two wheels with traction. Passenger front and Driver rear.

We were told to spin the wheels until the traction control came on and pulled us up. It was so scary, especially after what I had just been through.

It was VERY difficult for me to do. I wanted so bad to BTM my way through the obstacle. But sure enough it worked. It took a little bit longer than I would have liked for it to engage. It did, and I cleared the obstacle.

So, it think in soft dirt or loose gravel/rock it is an invaluable system. On slickrock, which grips like sandpaper, any kind of spin is a diff killer:D



hey bebe im with you i hate that way of ingaging our system . i think it sends such a shock wave thru the front end . im stickin with BTM . scary hell yea i bet you were worried :D

[HummBebe]

yep, I kept looking at him (thinking, you want me to do WHAT?), waiting for the 'BZZZZZ" tink tink tink. But it didn't happen. Phew!!!

[Hummie2]

So, it think in soft dirt or loose gravel/rock it is an invaluable system. On slickrock, which grips like sandpaper, any kind of spin is a diff killer:D


Sounds like you pretty well got it figgured out girl.;)

[Hummie2]

X 2

i had a 76 K5 blazer fulltime 4X that was 20 years ago and i couldant break it , i tried pretty hard too :D oh the gold old days ;)

I just did a quick count and over the last 40 yrs and I have owned 14 other 4X4s besides our H2 and H3.

The Hummers are the only rigs I have ever been afraid to spin the tires. Suprisingly they do very well without much wheel spin.... gots to love Trac Control. ;)

[f5fstop]

I haven't experienced what you guys have, but I'm really not too sure if wheel spin is the main problem. Imagine your front tires are both completely restricted against a large boulder, log, or in deep mud. You floor the engine, and the prop shaft has max torque that it can obtain with the 4-wheel drive system. The vehicle starts to rise, the case flexes, the pinion starts to ride up over the ring gear.
Could this be the actual problem? I'm just speculating here and trying to learn.:D

[HummBebe]

I haven't experienced what you guys have, but I'm really not too sure if wheel spin is the main problem. Imagine your front tires are both completely restricted against a large boulder, log, or in deep mud. You floor the engine, and the prop shaft has max torque that it can obtain with the 4-wheel drive system. The vehicle starts to rise, the case flexes, the pinion starts to ride up over the ring gear.
Could this be the actual problem? I'm just speculating here and trying to learn.:D

I think in my case, it is almost exactly what you described, with the exception, I did not floor it, but gradually increased throttle until I felt the vehicle begin to rise, BTM as well, to keep it from spinning or hopping over the ledge.

[Hummie2]

F5...

Yes, that is exactly the problem. The H3 housing flexes without wheel spin. Its just too light for the application. Any mods we could do to it to reinforce the housing ( like heavier, stiffer cover or billet steel bearing caps) would only be patches to something that was built too flimsy to begin with. Its like building a big house on a poor foundation- things don't stay square very long.

I have had this happen on big truck rearends that were speced too light for the service they were in. The fasteners that held the bearing caps would elongate under load and the results were the same as what we see here. Within 2yrs time all of those units on that order had experienced ring gear breakage.