Ok, so here's the whole story for those who are interested.
Bought the truck a year ago in Denver (I live in Seattle) Drove it out of town the day I bought it and the Trans went out in Cheyenne, snow storm, no cell coverage, on a flat bed $300 later to the Chev Dealer. Only had reverse, had all sorts of codes, many solenoid related. Spent a week there, previous owner took it back, took it to ATS, got a clean bill of health from ATS which I was told was NEW EVERYTHING. I got the truck back about 6 weeks later, drove to Seattle with no problems.
I had Idaho Rob flash me some tunes. Previous owner said it only had a "remove DPF tune" in it. My first diesel, friends told me truck was faster than sh!t. I sent the tune I had to rob and he said DONT DRIVE IT, said it was the WORST TUNE he had seen in 6 years of tuning the Duramax. He moved me to the front of the list and overnighted me the tunes, installed them, totally different truck. Of the 5 tunes, I have it in TOW tune 99% of the time. I don't pull sleds, race honda's, or take it to the track.
I have been on the phone with ATS numerous times since then with questions about heat, I see 200 degrees in town (before Transynd) and I've seen 215 or so towing a 6000# boat up hills to which they say was fine. That's happened a couple times.
It started last summer with the delay and hard shift into REV. Later the 2-3 shift started to occasionally hang, then MIKE suggested Transynd. That brought the temps down, and seem to help the shifts for a while. Now the 2-3 shift is always rough (after the trans is up to temp) and sometimes the 3-4 is acting up. REV still doing the same.
Since ATS the last time, the truck has about 7000 miles on it. This brings us to yesterday, I parked it last night out of limp mode but with the trans light on.
I'm trying to head down the most logical path. Idaho Rob and others have said that the tunes would normally have very little to do with that. I don't actually have a stock ECM tune, my truck only came with the crazy ruin your truck tune. Chasing down a stock tune would cost x amount of dollars.
I could take it somewhere and have them drop the pan, replace the E solenoid, change the internal filter and the fluid and give everything a good look under there. That could be one plan of action and cost X amount of dollars.
ATS isn't getting this trans back unless they cover 100% of everything, and I don't see that happening. The closest ATS place is in Oregon, 3 hours South. I've just had too much trouble with it. Not bashing ATS, I want to be a FAN I've just been let down too much. I'm all about the Suncoast stuff, I just don't want to drop and rebuild if I don't have to just yet.
This is where I'm at, trying to find a trans shop today- If anyone has any recommends in the Seattle area I'm all ears. There is a place called Pacific Torque where I bought the Transynd, I think they are one of the authorized Allison service centers in the area-
Thanks-