Here's my busted Differential pictures...

[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.

[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 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.

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

[NEOCON1]

Originally Posted by Hummie2

I still hold my breath everytime I see one spin 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.

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 oh the gold old days

[NEOCON1]

Originally Posted by 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

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

[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]

Originally Posted by HummBebe

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

Sounds like you pretty well got it figgured out girl.

[Hummie2]

Originally Posted by NEOCON1

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 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.

[HummBebe]

Originally Posted by 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.

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.