I gave in.....I was weak.....

[American1990]

Ok..... I gave in....I finally see why so many 2.9 guys swap to 4.0...I drove a 1992 4.0 the other day...and loved it...now I own it and plan to swap in in my 1989 4x4 short bed/standard cab. I plan to use my original tranny and everything back. I plan to also swap the ENTIRE harness so no cutting has to be done for plug and play. The only question I have is.... For the wires that go to the fuel tank and also the transmission do i also have to swap those over with the 4.0 harness or can they plug right into the 4,0 harness connectors with no problem? They both are EFI.... any info is appreciated.

 

[AlaskanRider]

I swapped the entire harness when I did my swap, and the 2.3L fuel pump wires plugged right into the harness of the 4.0. Mine was a manual. The colors on the wires were exactly the same for the fuel pump. Swap was 1990 4.0 into 1991 2.3 ranger.

I also swapped out the whole dash for the tach, which wasn't bad at all.

The harness was really intimidating, but its not as bad as it looks once you get started. Just make sure to be methodical and its a piece of cake. It looks like black magic but its nothing to worry about. I didn't get to take it out of the donor, so nothing was marked and I still was able to figure it out.

Now I mark all the plugs with a black or silver sharpie before disconnecting and it goes back together alot faster.

Best way to know for sure if it will work is to get started ASAP. Good luck! Its really not that big a deal to splice a couple wires.

 

[American1990]

How about your fuel lines? Were those simple plug and play? or is it better to just swap over everything?