Before I resort to pulling and replacing the trans, I thought I should ask if there are any simple causes for the tranny to not shift into 3rd or 4th. Shifts from 1-2 OK, but once the speed is high enough to shift to 3rd, the tranny disengages and the motor is freewheeling until it is shifted back to 2nd or the car speed slows down enough to fall back into 2nd gear. Anything I can do to test / check it without pulling the whole transmission?