doing a gas engine to diesel transmission matchup

[Ezra]

what would the problem be matching up a diesel automatic transmission to a gas engine. Im looking at putting a pre 70's 454 in front of a 6.2 diesel automatic. any ideas.

[davester]

Find out the specific type of transmission that is in the truck.  It's likely a 4l80e, but I don't know for sure.

 

After this, you should be able to google for how to mate up the engine with the transmission.  You may need to find the "type" of engine/block to make google results better.

 

Assuming you can bolt them together, and get a flexplate and a 4l80e torque converter with a reasonable stall for the engine (maybe later model HD trucks, from say just before the switch to the GMT800 platform), the final thing will be the transmission controller.  The 4l80e is electronically controlled, and generally have a tcm that uses input from the ecm to aid in controlling shift points and torque converter lockup.  Your engine won't have a ecm to get these signals from, so you probably would have to spring for a standalone controller.

[Ezra]

I was thinking of running TBI on the older engine. the truck its going into is a 92 GM 4x4 short box. I was going to try and use as much of the modern stuff as i could

 

[riverbanks]

Short box?that is diesel tranny,92?

[Ezra]

this is what the pickup looks like

[Ezra]

the diesel transmission is what im going to put behind the 454. as a combination. i want the extra duty transmission to take the power of the engine. 

[riverbanks]

What year is the tranny?

[riverbanks]

Unfortunately,there is no difference for gas or diesel tranny's,until the Allison was introduced,either,th400 or 4l80e

[Ezra]

i think the tranny might be the same age as my pickup. not sure. i haven't gotten either of them yet and most likely not until spring. i was talking to another guy and he put his trans into a much older truck. he had to replace the valve body. This is what i was wondering since i will be putting the trans into about the same vehicle as what it came out of

[Ezra]

Thank you George and it is pre Allison

 

Edited January 7, 2020 by Ezra

[Ezra]

thank for everyones help

 

[riverbanks]

You got to pick a year and go from there,many changes in early 90's,th400 has detent cable to injection pump,later,4l80e needs the ecm cause a v.s.s was on the diesel engine

[Ezra]

well once i get my ducks in a row i will ask more questions and have more answers. Thank you again George. that detent cable would be like the older kick down cable used in the 70's?

[riverbanks]

Yep,the dilemma,4speed,or 3 speed,lots to think about

[Ezra]

4 speed