Strange transmission problem

[Mooseman93]

Okay heres a quick rundown on the issue.
2009 Tahoe SSV with the 6spd auto.
It had been parked on jackstands for nearly 4 weeks while i was getting everything together to to longtube headers etc.. etc..
While it was torn down i went ahead and dropped the transmission pan to install a new trans filter.
Last night i got everything back together enough to start it up and check for leaks and whatnot. While it was running I replaced the transmission fluid that was drained when the pan was dropped.
While it was still on the stands and running i figured i would put the trans in drive , reverse, etc. When i put it in gear there is nothing. It doesnt seem to go into any gear at all. No wheelspin or movement at all. Anyone else had a similar problem with their Tahoe? Any suggestions on what to check first. Ill check to see if there are any codes other that the emissions codes from removing the cats. Yes having it professionally tuned is going to be done this week , as long as it will go into gear and can be driven to the tuning shop. Im stumped on what has went wrong. I didnt unplug anything associated with the trans.
On the bright side it does sound Really GOOD.

I would start with a thorough review of the cable linkage. I know on my 01 Yukon XL it was a pain getting that thing out of the way to drop the pan and I actually damaged it in the process to the point that mine did something similar when I started it back up.

 

[JCope79]

I would start with a thorough review of the cable linkage. I know on my 01 Yukon XL it was a pain getting that thing out of the way to drop the pan and I actually damaged it in the process to the point that mine did something similar when I started it back up.

I didnt have to do anything to the linkage since the exhaust wasnt in the way. I was able to drop it straight down....while spilling atf of course.

 

[Floep]

My bet is the "gasket" o ring on the tx filter, missing, old one not removed or new one not in place, sucking air instead of ATF

 

[JCope79]

My bet is the "gasket" o ring on the tx filter, missing, old one not removed or new one not in place, sucking air instead of ATF

I dont think that is the issue since the weird shifting issue started before the transmission filter was replaced.

 

[BG1988]

I dont think that is the issue since the weird shifting issue started before the transmission filter was replaced.

sometimes changing the fluid makes it worse

 

[Meccanoble]

Did you find a lot of shavings on your magnet?

 

[JCope79]

Went to the transmission shop Friday.
Im waiting on the price list on my options.. Im hoping to get by with a torque converter and probably a new ECM for the trans. If we were going to keep this long term i would have it built but its not in the budget for that type of expense .

 

[JCope79]

Update on the transmission issue.
I have found a transmission at a local auto recycling yard. It has low miles considering the age of the vehicle it will be removed from. I am capable of doing the swap myself however my main concern is whether or not this type of transmission (6spd/6L80) is going to be plug and play so to speak. Does anyone on here have any experience with a setup like mine and could tell me if i will be able to simply swap the trans with the replacement unit, plug/hook everything up, and put it back on the ground and drive on?

 

[Kraig]

What year is the trans you’re swapping in?

 

[swathdiver]

Update on the transmission issue.
I have found a transmission at a local auto recycling yard. It has low miles considering the age of the vehicle it will be removed from. I am capable of doing the swap myself however my main concern is whether or not this type of transmission (6spd/6L80) is going to be plug and play so to speak. Does anyone on here have any experience with a setup like mine and could tell me if i will be able to simply swap the trans with the replacement unit, plug/hook everything up, and put it back on the ground and drive on?

Well, what was wrong with the original one? I don't know about every year or all the differences but do know the tails are different from 2WD and 4WD.

The Service Fast Learn Adapts procedure should be run on the new trans, just as you should have done to your old one after you changed the fluid.