Quote Originally Posted by 2500Ak View Post
The newer transmissions use a new PWM valve that gives it partial lockup which might complicate things, but you can swap out for the pre-95 valve (so it's either locked or unlocked).
I noticed that sometimes I get two levels of lockup, depending on how hard I push the gas going up a hill or under a load. I always wondered how that worked.

Cowboy, if you drive it with your foot instead of cruise and can push the gas pedal down a little the tranny will usually drop lockup on its own before grabbing third, at least thats how mine works. A bunch of my buddies with diesels have the manual lockup switches and i think it would be neat to have one too. They all have built sled puller transmissions though.