Its locking up at a good speed. There is an electrical port on the left
side of the trans. This connection requires 12 volts or so to trip the
solenoid in the valve body. The more throttle the later the converter
will lock or not at all. The pump pressure controls lockup speed. More
throttle means more pressure and is controlled by the TV or throttle
valve cable which is directly connected to the throttle. Lockup is
essential for increased mileage.
> I have a TH350 in my '85 with 350 engine. Anyone know what controls the
> lock-up converter and why it would lock-up at 30mph? If I accelerate kinda
> hard (1/3 throttle) it seems tp work fine and comes in about 50mph. Anything
> less than that it locks up as soon as it hits 3rd gear. I know this isn't
> old truck specific, but thought I'd tap someones knowledge.
> 1959 Apache Fleetside
> oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959