I have an 87 4-runner w/ a motor that I just rebuilt. After I got all the engine bugs figured out....rough idle, O2 sensor wire, etc...I took it out for a spin. It seems as though the torque converter is not locking up when it should. The motor is reving to about 2000rpm before the trans. kicks in and the truck starts to move. It seems to be ok once the truck starts moving. A few times when I was at a stop (still in drive) I could feel the truck try to lurch foward like it locking up then. Anyone have any ideas on where to start with this problem?

 

n/m....I'm stupid and didn't check my fluid level more than once. Once the fluid worked into the gears it needed another quart.