Wants to run away...

[John Boggs]

My 70 F100 automatic seems to want to run away at a full stop in drive. I have to step hard on the brake to keep from running over what's in front of me. It doesn't appear to be idling to fast and I was wondering if maybe there was something in the tranny that wasn't properly engaging (or disengaging) at stop. Thanks. John Boggs

[Like M. Fords]

Lets assume your brakes are fine. There is only one way that your drivetrain can produce the amount of torque you are experiencing at idle. That would be the combination of a low-stall torque converter & very low gear ratio in the transmission and/or rear end. The older automatics did not have a lock-up torque converter, so there is no direct connection between the engine and input shaft of transmission, just fluid. Are you able to idle up real steep slopes without any additional throttle? Do the rear tires want to spin in wet grass or loose gravel at idle? If you answer "no" then you probably have a brake problem.

If the brakes work at other speeds, then you might want to check your manifold vaccuum. If it is too low at idle, then your brake booster will not be able to do its job, making the work harder for you.

[tmyers]