We wanted to give our stock TH400 automatic transmission a few upgrades specifically for wheeling, so we made a call to TCI for a full manual reverse valve body kit with engine braking (PN 221201), deep aluminum oil pan (PN 228000), and some fresh TCI oil. A full manual reverse valve body isn’t for everyone because it essentially makes your automatic transmission a manual tranny, minus the foot-operated clutch of course. If you shift it into a gear, it stays there, no matter what. Another advantage is that you can easily toggle the shifter from First gear to Reverse when backing down a hill because the shift pattern is flipped. The TCI kit requires that the transmission be removed and partially disassembled, so it’s a good idea to do a full tranny cleaning and rebuild at the time of installation.