It ran pretty good tonight, it bogs down between shifts but I thought maybe it was my tune.
I was doing maf tuning tonight and all was well until I got on it hard one time, down shifted and now the thing wont move when I put it in drive. lol
I can put it in first and then shift thru the gears on into drive and it shifts but from a stop when I put it in drive it wont go anywhere. To the Trans shop tomorrow.
4L60E, right? If so, sounds like the Low/Reverse sprag clutch let go on you. It moves in manual low because the overrun clutch pack is applied. Which brings me to my next thought. If you are going to hammer on a 4L60E or 4L80E for that matter, pull it down to 3rd. It applies the overrun clutch and makes the unit stronger.
The bog between shifts is probably torque management, but I would recommend keeping it, especially with a 4L60E. Maybe tighten up the shift time tables to 0.250s at higher torque values. 3-4 shift in most stock tunes is zeros. With a 4L60E, I usually use 0.250s shift time and 30% torque reduction on both 1-2 and 2-3 shifts from 240 ft/lbs and beyond.
Last edited by Fast4.7; 09-28-2022 at 12:16 PM.