2008 H2 - Strange Encounter

[WikidPete]

Ok so a little background on this. I've had my H2 for about 9 months and it has approx 10k miles and still love it even with this weird encounter.

So I took a trip from Northern California to Arizona to pick up my military 3/4 ton trailer from the USMC Station in Arizona. I was towing the uhaul Auto trailer to load the 3/4 ton military trailer. As I was driving down I5 in the middle of the night I started encountering this weird issue. The speedometer kept fluctuating and the transmission seemed like it was stuck in 2nd gear, every warning light came on. This all happened all of the sudden like it was possessed. Pulled over stopped and restarted the car again thinking it will reset the computer.. Yet it felt like the transmission was stuck and wouldn?t switch gear as I speed up. Some of the warning light went out but a few still stayed on. I called onstar to find out what options I had being stuck in the middle of nowhere towing an empty trailer. They said that I need to bring it to the nearest Dealer.

So I?m trying to figure out what to do and it?s like 2am in the morning by now. I decided to try limping along the highway to the nearest exit and low and behold the transmission was switching gears fine again. I kept it under close watch as I continued my trip to AZ at this point the only error light was the check engine light. I kept checking everything after each gas stop and didn?t seem to see any weird issues.. As I got closer to Arizona the check engine light suddenly disappeared during one of the gas stops. The trip back I encountered no issues, like it never happened.

The only thing I did notice was the Transmission was running around 175F and at one point it hit 200F.

Sorry for the lengthy post.. Any of you guys encounter anything strange like this? I?m taking it in next week for them to check it out. I asked if they can pull the error codes from On-Star. They say that they can?t. That is weird..

Anyways still a great Truck!!

[mikejr]

OK...sounds like a similar issue my dad had with his 08 SUV. He was stuck in gear etc. Sounds electrical to me.

When I first got my 08 SUV I had issues with dash lights, locker indicator etc...all due to a chaffed wire which screwed up the BCM.

Now the said they couldnt find anything wrong with my dads truck, had it for a week and took everything apart and even consulted with the hummer engineering team. They thought that maybe taking things apart and putting them back together might have fixed it.

Again...i think its electrical. Everything is run by computers on these things.

[CONRAD II]

It sounds like the same problem I had. If I remember correctly there is something in the ignition that needs to be replaced or fixed. BTW the problem will continue untill you get it fixed.

[Vettster]

Onstar sucks!
How could they let you drive the vehicle when it was acting like that?
A dying/not shifting vehicle is obviously a safety hazard.
I didn't even activate my "free" year. And when it was over they had the balls to send me a bill for the subsequent year.

[pdxhummerguy]

I had the same problem. It was the ignition.

[WHOSNEXT]

Originally Posted by pdxhummerguy

I had the same problem. It was the ignition.

ditto

[WikidPete]

Yeah I asked them where the closest Hummer dealer was and they said LA.. I was still 200 miles away.. LOL. And I think the only time I use it is when there is an issue.. and they always say take it into the dealer. Anyone else get any good use out of it?

Originally Posted by Vettster

Onstar sucks!
How could they let you drive the vehicle when it was acting like that?
A dying/not shifting vehicle is obviously a safety hazard.
I didn't even activate my "free" year. And when it was over they had the balls to send me a bill for the subsequent year.

[HUMTECH]

Def ignition switch, common. Ign 1 power runs through the ign switch to the transmission control module, the switch fails and the transmission goes into limp mode. Usually accompanied by 5 trans codes, any gm tech should be familar with this and there is a tsb on it as well.

[BigPoppa1411]

Originally Posted by WikidPete

Anyone else get any good use out of it?

I havent had to use it for any mechanical issues, but they were great when it came to getting help for 2 vehicle accidents I came upon on my way home. I live out in the boonies and there isnt much traffic on my road late at night so it was helpful.