Hello Everyone!
I'm getting prepared to swap a 351W/ ZF5/ Manual shift T case into my 1991 F150.

Attachment 281443

The truck came to me with no engine ( formerly a 302) an AOD, and a manual shift T case. The drivetrain has two donors, the engine is from a 1997 F250 HD, and the transmission and transfer case are from a 1990 F250 (also a 351W truck).

So, my next step will be pulling out the dash to swap in the clutch pedal assembly. I kept the entire dash harness, engine harness and ECM out of the 1990 F250, as well as the Dash harness, engine harness, and ECM out of the 1997 F250 HD. What dash harness so i need to use, or is my F150 harness sufficient? What ECM to use? and what engine harness to use?

Also, worth mentioning, i do see the 97 engine harness had a 3G alternator setup, that was the alternator i was planning on swapping to as this project progressed, would that make a difference in my engine harness choice?

 

If you have everything from the '97 use it, but you must have EVERYTHING including the dash cluster.

 

So Conan, what you are suggesting is making my 91 believe it is a 97 F250. Swapping the entire dash harness, as well as the engine harness. This now brings up several more questions.

First off, the 97 is still speed density, not Mass Air. idk if that changes your opinion or not.

secondly, do i need to use the underhood harness ( the one that loops from the drivers fender, across the core support, and to the passenger fender) , and do i need to use the chassis harness from the 97?

Thirdly; my f150 is a power window, power lock, tilt cruise AC truck, whereas the 97 was a stripped down no frills model. can i still get all my accessories to work?

fourthly; the 97 was a 2wd automatic truck; do i need to get a different ECM to work with a 4x4 manual?

Fifthly, i was planning on ditching the RABS system, i know ill need the VSS to run the speedo, but can i still can the rest of it?

Lastly, the 97 cluster is low level cluster. ive done the swap to a factory tach cluster on other trucks, but what year/years can i get one from to match a 97?

thanks for your input.

 

I assumed they were both SD since you didn’t mention the ‘97 was mass air.

I gathered that you should use the engine harness and not the chassis harness. AFAIK they wouldn’t be plug and play

Yes since you are still using the harness from the ‘91

No. The transfer case ( manual or electronic) isn’t tied into the system at all

Why? If it isn’t broken don’t fix it. Wouldn’t the speedometer still be cable driven in ‘91?

I guess what I said depends on what dash you are going to use.