88 4runner
2.4l engine
auto
dual t-case with inchworh adapter which was all installed per inchwrom instructions.

problem:

When I start going up an obstacle lets say 30 deg. or more my vehicle stops moving. The engine is still running it revs fine. the t-case is in gear and auto is in low. we tried every gear combination possible even reverse and the vehicle will not move. fluid level was checked.

When I am on the trail or even climbing a hill it drives fine in all gears.

Whats the problem?

 

Jim at Inchworm said to overfill a/t with up to 6 qts. If anyone is interested.

 

Sounds like the fluid is draining from the transmission. Overfilling should solve that problem.