2002 Ford F-250 4R100 transmission issue 1st to 2nd
Posted: Sat Jul 18, 2020 7:59 am
My truck has 196k miles on the original transmission. Had a mild tune on it. Started to not upshift from 1st to second gear unless I let off the throttle. All other gears work fine and reverse. I took the tune off and returned to stock and it is still doing it after it gets warm. Tranny fluid is clean. From what I read it could be the solenoid pack or valve body. Looking to see if anyone had same issue. I don’t want to do a full rebuild unless it really needs it.