I am working on my Son-in-law’s 1989 D100. It’s a really nice long bed 2wd. I swapped the 318 for a 360 magnum. It turned into a real job. I put an Assault racing intake and a new brawler carb. I used brand new MSD ignition. The fuel module in the stock tank had broken connections so we also installed a Holley billet retrofit assembly with a Walbro pump. After all of the goodies and cleaning up the engine bay the first test drive brought a slipping transmission.
Now I am going to put a transmission from a 1994 350 van with overdrive. I am not sure which transmission it is. I am going to use this one because I can swap the old 318 for it. The van ran and drove great but the engine smoked. I know it would be better if i knew exactly which transmits it is but I am a die hard Chevy guy. I am big enough to realize I have a lot to learn about this truck. So, what better move than ask real enthusiast that are experts. What can you guys share before I start on this new project. I read that the linkage and throttle mechanism for the transmission is the same. I also read I can run the OD on a switch to engage it on the interstate. My son in law is a Marine and I have to drive it on a 13 hour ride to give it back. I would like to do this so he can drive it anywhere any time and save some fuel. The magnum makes decent power. If it had a gear in it I think it would run pretty good.
Thanks for any help.

 

It would be the 46RH trans. You can get kits so that O/D, and TCC work without having to have a computer.

 

should be 46rh. if you still have access to the van you can run the vin to double check. you will likely need 2 switches. 1 for overdrive and 1 for lockup torque converter.

 

Thanks a bunch guys! I am going to take a look at the VIN. I have an agreement with the junkyard that has the van. I can get any and all parts off the van I need as long as I give him anything I don’t use on the pickup. I am ok with that because this is the only Chrysler I am going to be working on. Will the slip yoke out of the current tranny work? II can’t be sure if it is a 904. A buddy of mine that races Dodges looked under the truck and told me that. I read the OD is a couple inches longer. I have cut a few driveshafts over the years. As long as you mark and clock the plug in the same position they won’t need to be balanced. I can also notch the crossmember if I need to. When I get to wiring the switches I will definitely need your help.

 

have look here. Instructions on how to do it. There are also complete kits available for just such an occasion.

 

Thank you very much. That’s the article I stumbled across when I started the magnum swap. This truck has really tall tires on the rear. I think the mph figures to upshift would just be a few mph higher. It has a 31” tire instead of the roughly 28” tire it came with. It will still respond the same to throttle position lowering vacuum then it will drop out of lock up and OD by itself.

 

 

hopefully that is a older picture of under the hood because it almost looks like there is multiple things that don't look right.

 

You must mean the frankensteied upper radiator hose!

 

Hahaha! You are right that’s what happens when you have junk laying around and just want to start it.