Thanks guys, just want to make sure, when I do the test in Drive I will record the PSI even though the RV does not move in Drive or second. It only moves in 1st and I have to shift myself to 2nd and than shift to drive.
Yep that's the way to do it. It should actually read the same no matter what forward gear your in if your stopped. It's just that if it's over 1.5 psi it'll automatically shift into higher gears even before you move. Good luck. Hopefully it's something simple like a stuck governor, not a broken sprague.