So, my 04' H2 has 46,557 on it. My driveway is flat. I go to leave the other day, put it in reverse and CLANK / ARRRRRRRRRRRRRRRR and it whines like a banchee in Park, Reverse and Neutral. There is no-longer a reverse gear but drive and all low gears work fine.

I took it to a friend who owns a very good local Transmission shop. This guy is no sleeze, I've known him for 20 years, since I was working in the auto industry.

He tells me that the transmission in the H2 is the same one used in the heavy duty Suburban and that the "Shell Gear" is fragile. He says its very comon for them to break. So, if you tow with your H2 at ALL. Go see a tranny dealer you trust and get rid of the stock "Shell Gear" there is a good after market HD one to use instead.

Just a FYI. I don't know if this applies to 05 and up, but I do know it applies to 03 and 04.

 

what exactly is a shell gear?

hopefully it doesnt apply to 05's..I tow an RV with mine.

 

Yeah... this is a problem.

http://www.automotiveforums.com/t208603.html

http://www.justanswer.com/questions/...burban-5-7-ltr

From what I can gather reading forums, it's a pandora's box for Chevrolet. I can't pin down which years are effected but it's my understanding that the 6.2 came with the HD gear installed. So chances are if you have the 6.2 (from my understanding) it's safe. But, for the sake of your own sanity if you tow, take your truck to a tranny shop you trust and ask em if your year is effected.

I'm going through the 7th level of beauracratic hell with GM trying to figure out if there is any help from them on these things. So far nothing but I guess the Hummer factory guy in Central California is abit hard to contact.

I'll post an update as soon as I have one.

 

What is the name of the company that produces the automatic transmission for 2004 Hummer H2 ?
Pleasure to meet you all

 

That exact same thing happened to me this morning! (05, 90k's) We pushed, then drove it to a tranny shop, and they say the same thing. Replace the stock with a heavy duty one. They were actually surprised that GM would put in the same as the Suburban, although the H2 is like twice the weight. Thanks for the info, you saved me some guessing and $$$.

 

How much is it to replace a shell gear?

 

Glad I own a 2006. I didn't see anything about the 2006 H2, guess that the problem ends at the 2005 H2.

 

So I called around to see how much it would be to replace this shell gear. Guys were telling me that its similar to the rebuilding of a transmission. Reason being is that they have to tear the whole transmission apart to get to the shell gear in order to replace it.

It was presented to me like 1) pay a lot for labor to replace a shell gear or 2) pay a little more to rebuild the entire transmission...

If this is the case, I guess I'll just wait for mine to explode...

 

I think there is no much difference between the transmission of 2005 2006 and 2007. It is all the 4l65. If you have a supercharger, 37 inch wheels or tow a lot it will brake. This transmission is simply to weak for the car

you can find some upgrades www.transmissioncenter.net/4l60e.htm

 

Appears 2002-2007 H2s had the problem trans...if you believe WIKIPEDIA....

Atleast its somewhre to start....

http://en.wikipedia.org/wiki/Hummer_H2

One more thing to take into consideration during my current used H2 hunt...I can smell my H2 out there...somewhere....now to just find it!