2.9 to 4.0 swap

[lewiusmc93]

hey everyone, i found an OHV 4.0L out of a 90 ranger and wanna put it in my 87 ranger. ive read the swap articles in the technical info section and it seems pretty straight forward. in the 4.0 conversion faqs, it say to put an 89+ into an 88- you need to replace the dash. it doesnt say why that is so im sceptical if i have to since im goin from ranger to ranger. any help is appreciated, thanks

 

[Surrey]

In 89 they changed the dash. I assume the wiring harness from the 4.0 wont be compatible with your old dash.

 

[adsm08]

The mandate for swapping the dash is because the wiring connection is not compatible, and a dash swap is the easiest way (you know you need to get the 4.0 engine wiring too, right?), but there are other methods.

I am in the middle of the exact same swap (just set my engine in today and was trying to get the trans back up when my last flash light died). I started looking at splicing a piece of an 89+ dash harness into my existing one to get the right plug on the end. The more I looked at it the more I realized the plugs that I do have on the piece of harness I have for things like the ignition switch, turn signals, etc, are all the same as the harness I already have. I am thinking I will be able to just take an 89+ harness and plug it in to the older dash, maybe only having to swap a few plugs and splice 10 or 15 wires, instead of the 30 required by my original idea.

Keep an eye on my first build thread in my sig for more details.

 

[lewiusmc93]

alright guys, thanks. i think ill be able to find everything i need at the scrap yard down the street, all the help is appreciated.

 

[adsm08]

The fuel lines are also different. I figured out how to hook the 4.0 lines right into the existing 2.9L lines though. You just need the line fittings from a 2.9 truck and about a foot worth of the 4.0 rail lines.

 

[SenorNoob]

adsm08, after reading your thread and that post. I just realized how very similar our minds work when working on these trucks. I did almost the same thing for my fuel lines. Only difference is one of mine has a short section of rubber hose. I did just cut my wiring under the hood though, cause I HATE working with anything in the dash deeper than the radio.