Transmission problem?
I've noticed some issues with my transmission lately (4L60E with TransGo shift kit & 3 washers). When driving at about 55 mph and pressing the gas pedal a bit, the transmission seems to stutter. (If I stomp the pedal at that speed, it'll shift down just fine & take off.) I've also noticed lately that when cruising at interstate speeds, 70+, it seemed like it was running at slightly higher rpms than normal. The other day I confirmed my suspicions, when it completely went into overdrive while just cruising with the cruise control set. It's not staying completely in 3rd gear, because if I manually shift down, the rpms are a lot higher. Seems like it's somewhere in between? Is this maybe something to do with the stall converter? I really don't understand much about transmissions.