Transmission

I have same problem with a 95 4runner 4wd 3VZE engine and A340 H tranny. I had previously had a real bad problem with all gears "neutralizing" where car would rev up but not move forward or rear in any gear. I spent $ 1,500.00 for transmission and transfer case rebuild, and problem not solved. After months of research, I found out there is a "valve body" which is a an electronic plate inside the transmission drain pan right above the transmission filter. These valve bodies have solenoids which act as mini pumps inside transmission. I ordered a kit through a San Antonio, TX independent distributor (# 1 solenoid, # 2 solenoid, and a so called "lock up solenoid". Kit comes with full details how to replace those three sensors. I did job myself one afternoon..no problem. 4runner works like new now except for the reverse which acts as you mention. There is a fourth solenoid in the transfer case (not transmission) whcih was not part of the "kit" I bought. Although I'm not sure it is the cause, after replacing the other solenoids, the fix was dramatic on the forward gears. I'm currently researching if solenoid # 4 may be the cause of the reverse gear still not working fine.