6l80e shift problems

[Paintbytony]

So I have an issue with my 2013 5.3 with a 6l80, at WOT 1st 2nd and 3rd shift great but I have to let off to shift into 4th. Second problem is after about 10 miles or so when I slow down it will not shift back into 1st until almost a completely stop, this condition only occurs when the the truck has warmed up, I am running the transmission lines tandem through the rad then through an external trains cooler. Last problem is the converter locks in and out at cruzing speed 45-60, I'm very new to HP tuners and just bought it because if the local tuner shop can guess at it for 100 bucks and hour I guess I can guess as well.

Tony

[5FDP]

Almost sounds like a internal issue with the transmission itself. I don't know how tuning it will make it work any better if it pyhsically won't downshift on it's own to first gear once warm.

[Paintbytony]

I was fearful of that, everything shifted well until I let the tuner shop have it for 3 days

[5FDP]

Post the tune file you have.

I want to compare it with my stock files and see exactly what they changed. It could be possible that they screwed up the tune and made it do this.

I didn't know you had it already tuned, maybe I missed that part in the first post?


If something is so far out of whack it might be best to just find a stock tune file or I'll post my 2012 file and have you just copy over all the stock data again. Then reset all the adpats and take it for a drive and see if it acts normal again.

[LSxpwrdZ]

I would suggest flashing the transmission back to stock to start with, then work from there. Also double check that you have plenty of fluid in the transmission. They do not like being low on fluid.

[GHuggins]

I was fearful of that, everything shifted well until I let the tuner shop have it for 3 days

As stated, post the tune. Something is wrong. Is your truck stock? I don't understand why they wouldn't have noticed that.