Im new to these forums so this may have been answered already. I have a 06 H3 I5 that is having some shifting issues. The engine will rev up and the truck will move but it does not shift gears. The only remedy to this that i have found is to let it warm up for about 10-15 mins. This started about 20K miles ago but has gotten progressively worse. I have had no other issues with her and i am at 101K miles now. Any ideas would be greatly appreciated. Thanks.

 

I'm sorry, but I gotta ask....WHY would you let a perceived problem go for 20,000 miles before doing something about it?? Especially a big ticket item like a trans!!
Check your trans fluid for coolant cross contamination from a defective radiator.

 

20K ago it started? WOW

 

its not the rad or it would have died long ago!! 20k huh.

id look at a rebuilt tran and a new rad to be safe. didnt flush it huh,20k,wow

 

maybe i should clarify, it did it once 20k ago. And, by progrssively getting worse, i mean its done it 3 times in the past two months. The radiator was changed out back when it had 15k miles on it. No angry wrench codes come out either. Its very intermittent and does not happen when i let it warm up.

 

dump the juice and pray.have a shop check it. what else.

 

My 07 shifts all the time, I have only had it for 2 months and I hate the way it shifts constantly, I took it back to the dealer and they did nothing except tell me that they have had problems with them. I told them GM has always had transmission shifting problems, my 89 iroc did the same thing as well as my 91 1/2 ton. My old 78 chevy truck would do the exact thing you are talking about when it was cold and it turned out to be the front pump going bad. I have never been back to a car dealer for service for the since the last GM product I had back in 92, I should of learned back then. 2 months of ownership and I have spent 4 days at the dealership for problems. My wife says "you should of bought the MDX"

 

i never have much luck searching but i can tell you that since july,09 ive been reading every new thread. cant remember many for tranny trbl that were not related to the bad rad problem.
my thought is they shift when programmed to and a heavy foot will cause a lot of shifting.
i drive a lot around 40 -50 where i live and obviously get some tqc lok/unlok and maybe down shift in that range, normal.

 

If you bought it used the pcm might have been altered also if its shifting funny.

 

Thanks for the help i will try to look into this weekend.