I'm in the process of putting the engine , transmission and running gear out of my wrecked 93 into my 1973 W100 swb. What I want to know is what's the best way to control o/d on the 518 tranny with out the computer . I would like it to still be automatic and be able to push a button to take it out of o/d ?

Do the POT install... the OD button will still work, and its set manualy other than that

The Pot fix just takes place of the TPS you stil need computer input to use that. I want to be able to use o/d with no computer or tps. I read about installing a pressure switch on the transmission but was unclear as to what pressure port to put it in and how to wire it up ?

There is an article in the sticky about using govenor pressure that might be your only choice.

http://www.dieseltruckresource.com/d...d.php?t=156988

Any other thoughts on this ? I know there's some good tranny guys on here. I think the pressure switch should work . Just didn't know if there way a better way ?

While laying under the" BUS" i looked my trans., & rear end for nos. The rear is a 3.07, the trans(i think) is a 3 speed . I was think'in about a 518 , then some one told me " you'll need a computor" MY thought is now on hold.So i would like to hear about the pressure sw., method also, plus any cutin ,or weldin to be done under rhe trk.

Run it to a twelve Volt power source through a toggle switch, you can then run the overdrive manually

hey 454, the o/d ,if it shifts elec., could this be done by wireing it through the tach??