My son ran my '07 Hummer H3 out of gas and after we put gas back in and got it started a new problem started. The vehicle starts fine. I put it in drive and start going. Shortly after that it completely disengages from drive and it's like it is in neutral but still in drive. There's no gear from D 3 2 1--nothing and no reverse either. If I shut the vehicle off for a about 3-4 mins. and then start it again, it will drive for a while and then the same thing happens--it basically shifts itself out of gear again.

Any thoughts? I'm thinking it's related to running out of gas so maybe some kind of sensor issue but can't figure out how to fix it.

 

Memories,
Many years ago i let my son use my van. They had a way of destroying transmissions,rolling forward,pop it into reverse and floor it to maximize rubber burn,etc,etc.
You need to check,smell the fluid. If the level is good you probably are in for a rebuild,thank your son and let him buy his own car.
My son never got the keys again.

 

The fluid is done for sure (shifts fine when cold, when the fluid heats up it breaks down)
Drive up to your local parts store and have them pull codes?
Torque converter? Shift solenoids?
If no codes, start with a trans flush, drop the pan, clean it out, and install new filter & dexVI.
I have a feeling your son did more than run out of gas. GL

 

Just for fun, disconnect the battery for about 15 minutes. You can put the transfer case in neutral. Perhaps that is what is actually happening instead of there being a problem with the transmission. It's worth a shot.

 

sounds like transmission,agree with happythree smell the fluid and dark color.

 

Glad you mentioned the color. Black transmission fluid which was my first major concern but didn't feel any metal in the fluid so that made me feel better. I didn't notice any odor but didn't really smell it either. What odor am I looking for? Burnt I assume?

 

By odor is hard to tell if u dont khow how transmission fluid smeels when is new, but if u have dark color in u transmission oil is not good news as for metal in automatic transmissios u probably not goin to find any all depends whats damage cause auto trans. Have compound discs inside and to my knolege thats whats wrong with u tranny theres some metal gears on the tranny but discs go bad first running out of gas wont do that . Driving like a maniac would lol... Also changing trans. Oil improperly I always use on tras. OEM oil nothing else manufactures know those compounds on the discs and I do not recomend any magic oil for auto trans. Motor,manual trans. Differentials,t case,work different stick with OEM oil for autotransmissions.

 

I guess the color is from non metal parts like bands and chutches that got destroyed by misuse and abuse. You will find the pieces in the pan.
Sorry.