So today, I changed my transmission oil and filters.

While I was at, I installed an ATS billet channel plate, with their billet accumulator pistons and thicker accumulator plate.

I also installed a Suncoast solenoid pack.

I downloaded new tunes from Ray to take care of all those transmission changes also.

So I got it all put back together, put in new fluid, and took it for a test drive.

It shifted great and then suddenly went into manual mode, shifted down to 4th, and then stayed in 4th.

No 1st, 2nd, 3rd at all.

At a complete stop, still in 4th, would not shift down.

I tried getting it out of manual mode, and it would not shut off.

So I drove it home in 4th from the shop at work (we have a lift) about 15 miles.

Shut it off and then started the truck again, and now it's out of manual mode and back to normal, I think.

Another thing was that on the MM3 monitor, the trans temp was stuck at 123.4, and the Trans pressure was stuck at 240.

When I started the truck after getting home, it went back to normal, showing 160 temps and 150-170 pressure.

I haven't gone for another test drive.

I want to wait to see what you all will suggest.

I do have alpha and, so I thought about a trans relearn.

Any suggestions would be appreciated!