07 Yukon transmission shifting issue

[bigchaseusmc]

I have an 07 Yukon 4wd just recently the transmission is not shifting right. Every thing was fine parked it over night and when I got in to go to work in the morning. It wasn't shifting right. It seems like it's not shifting out of 1st gear. Under light acceleration if I let up on the gas it shifts. I had CEL but it was for an evap leak minor. So I disconnected the battery and left it for a couple of hours while I was working. Shifts better but still not like it should. Seems like it's not shifting into overdrive. It's served me all 250kish miles on it. I've had it since 60k. Fluid is full and definitely needs a fluid and filter change. Would it be worth changing the shift solenoids while I'm in the pan? Any help would be appreciated

 

[Doubeleive]

I have an 07 Yukon 4wd just recently the transmission is not shifting right. Every thing was fine parked it over night and when I got in to go to work in the morning. It wasn't shifting right. It seems like it's not shifting out of 1st gear. Under light acceleration if I let up on the gas it shifts. I had CEL but it was for an evap leak minor. So I disconnected the battery and left it for a couple of hours while I was working. Shifts better but still not like it should. Seems like it's not shifting into overdrive. It's served me all 250kish miles on it. I've had it since 60k. Fluid is full and definitely needs a fluid and filter change. Would it be worth changing the shift solenoids while I'm in the pan? Any help would be appreciated

big maybe.....
one thing that can affect shifting is the MAF, clogged cat's
if you have no suspects there then it's probably wise to drop the pan and inspect for metal or other material.
if it looks clean, you might be able to get away with just solenoids and a flush. the solenoids can be tested while you have the pan off
@NickTransmissions

 

[bigchaseusmc]

Well after a couple of miserable days crawling around on the ground in my driveway, I got the filter and solenoids changed. Shifts better than before not so hard. But still not shifting into 3rd/OD so time to get the tranny looked at. I've had too many back surgeries to swap it myself in the driveway, not to mention I really don't want to. The Mrs. has been out of work since she had our twins, so I don't want to get into a new truck payment at the moment. Let's see what a rebuild/ rebuilt tranny is going to cost me.

 

[Joseph Garcia]

I'd wait for @NickTransmissions to reply, as he is our resident transmission expert.

 

[Coleyslawn]

I would like to chime in on this. I was having the same issues you are having. I didnt drive it for about a week and the battery just went dead due to the back door not fully being shut. After a new battery was installed, I cranked it up and all of a sudden, the TCM would quit communicating . After extensive troubleshooting the power points, grounds, and the can bus, I finally replaced the TCM and it is like a new vehicle.