Originally Posted by StrokeThis 7.3
Did you ever figure out what the issue was, have a slimier issue. Parked the truck over night and woke up to no gears what so ever.
StrokeThis, I had the same problem with my tranny & recently just took it apart. It turns out I had blown the coaster bearing in the trans assembly & my coaster drum's lip seal had been damaged from original assembly from the factory. If you know how to work on transmissions, see if you have any trans. DTCs. I don't remember the DTC numbers, but the 2 I had were: Gear 3 incorrect ratio
, & Error 2-3 shift
When I dropped my pan, I found fragments of the race & ball bearings from the coaster bearing & a bunch of junk stuck to the magnet. I'm being told this is a common problem for the 4R100 whether it's being used for street/strip or excessive towing with stock internals of the trans.
Don't let the appearance of the ATF on the dipstick fool you. Mine appeared clean & up to the level it should've been, but when I dropped the pan it was almost purple & smelled cooked.