2.9 to 4.0 swap

[yewwoodtree]

im considering swapping my ticking 2.9 to a 4.0 engine. And i just had a question on the wiring. Do i have to take my whole dash apart and swap all the wires that are under there? or can i splice the harnesses at the firewall? What would be the easiest? I have already done a head swap, and changed 2.9s after i hydrolocked the last one, so i know the engine pretty well.

any help would be appreciated

 

[CJREX]

You have a 1990 model. On a '90 BII it's virtually plug-n-play so I can't see the Ranger being much different.

Swap the engine harness under the hood and you may have to do a couple of wires by the alternator. Dash should be fine.

Your fuel lines should even plug right in.

With a '90 there's no way I would ever bother with another 2.9 since the 4.0 is such an easy swap. 2.9s are getting scarce and the junkyards are full of good 4.0s bolted to dead A4LDs.

Just be ready to possibly swap trans too depending on which one you currently have.

Trans code "M" on the door sticker and you're golden.

 

[bobbywalter]

sometimes fuel lines can vary, but the system from a 4.0 truck is makes it simple.

 

[yewwoodtree]

ya, swapping in another 2.9 was not one of my better decisions lol. I do have the "m" trans code on the door. cant wait to get rid of that pos 2.9 and feel the 4.0 power!

 

[Mechanickid]

How hard would this swap be on an 88 model? I have an Fm146 trans. srry to thread jack.

 

[99RangerKrazy]

Should be close to the same as a 1990. There might be a few different wiring hoops you need to jump through, but it'll bolt in. However, a 4.0L will kill that FM146, unless you really baby it. But an M5OD swap will fix that for ya.

 

[AllanD]

The '88 is still a gen1 and there is little in common in the way the trucks are wired.
You are going to need to deal with a full generational change in the wiring.

Not to say it's "impossible" far from it. but a swap on an '89-92 is not materially more difficult than replacing one 2.9 with another.

swapping the wiring harness (IF you get the proper donor harness)
for the job.

"Proper" in this case is from a 1990-92 RANGER.

there are differences in the Explorer wiring, mostly related to the way the wires are routed for the various power accesories that just makes things a moderatly sized PITA.


I made my life a lot more difficult by specifically choosing a 1993 Explorer
as a donor for my swap into a 1987 supercab.
But I had my reasons, I wanted the "top mounted" relays for quicker access
to the relays and to integrate my own accessories (Power feed for communications radios and auxilary lighting) and I needed the relay sockets that were intended for the ABS system.

I also wanted the 1993 engine management as it was the first year of
the "smart" EEC4, but yet did not have EGR, it's troublesome sensors
or SEFI with it's EXPEN$IVE and more troublesome sensor.


THE true beauty of swapping a 4.0 in where a 2.9 has been is mechanically if you are swapping the engine WITH engine accessories the differences are limited to the throttle cable, Radiator hoses (different routing) and heater hoses (Longer)
and A/C lines

Motor mounts, Y-pipe, and bellhousing patterns are the same making it mechanically the EASIEST of swaps even on a gen1 truck where the wiring is a bit more intellectually intense.

AD

 

[jaymegriffiths]

i am actually fairly close to performing an identicle swap, have found a donor, just need to get it payed for and brought home. first i must safety my new truck, so hopefully ill get it done quickly so i can begin the swap. AD, if changing an 88 to 89-92 is the place in the tech library explaining the wiring changes done on the drivers side near the firewall the ones WE will have to worry about? Beside the mechanical? and can i take the tranny out of the donor without changing t case? if i can put the tranny w/o the t case, is it a direct bolt in? if i cannot put the tranny in w/o changing the tcase can i put the new t case in easily? without fabbing up a new crossmember? and will the electronic shift 4wd plug in from the new t case to the exhisting switch, as my truck has e shift already? PS both trucks have manual hubs... dunno if this matters. also both are 5 speed. and i wanna make sure, as its a PITA to change ranger trannys. Mostly cause im not sure how to de-attach the master cylinder from the line, nor do i want to im told,as bleeding the clutch is very tricky, "im told"
sorry for the thread jack, but maybe if my questions get answered they can be of help to you!

 

[RangerSVT]

and can i take the tranny out of the donor without changing t case? if i can put the tranny w/o the t case, is it a direct bolt in? if i cannot put the tranny in w/o changing the tcase can i put the new t case in easily? and will the electronic shift 4wd plug in from the new t case to the exhisting switch, as my truck has e shift already? PS both trucks have manual hubs... dunno if this matters. also both are 5 speed. and i wanna make sure, as its a PITA to change ranger trannys. Mostly cause im not sure how to de-attach the master cylinder from the line, nor do i want to im told,as bleeding the clutch is very tricky, "im told"
sorry for the thread jack, but maybe if my questions get answered they can be of help to you!

Grab the trans from the donor, its stronger and will bolt up to your tcase, however, the tcase from the donor (if its 1354) I would hang onto, it is a very desired case and would be a better choice. Honestly, I would grab the trans, tcase and front dshaft and upgrade all...I'm not sure about xmember issues, but grab the donor xmember to be safe, not sure on the plug for the tcase, may have to re-pin...Releasing the clutch line can be a little tricky, but go to your local autoparts store (preferably autozone, they know their stuff) and ask for a ford hydraulic clutch line release tool, should cost you a couple of dollars (5-7 bucks), ask them to give you a demo on how to use it, they'll be happy to show you on a clutch line they have in stock if they have it...once released no fluid will spill out due to the design, so no bleeding is needed...
SVT

 

[Fordfreak11]

I'm having ghost problem with 91 ranger 5 speed 4x4?

Hi new here but I need help. I'm pretty good at figuring stuff out but this one is beyond me. Ok I bought a 91 extended cab Ford ranger 2.9 5 speed 4x4 stock. When I would drive it it would have hesitation when you would give it to much gas while trying to get to speed and on hills would drop speed from 70 to 50 in no time. Like it had no power at all. If you let up off the gas a bit it would smooth out but not gain anymore power, but if I push the clutch in I could Rev it up with no problems at all. As soon as I would let clutch back out and give it a generous amount of gas to gain speed it would hesitate again. It was really hard to get up to speed to even shift if you give to much gas. I replaced fuel pump, fuel filter, plug ( motor craft), wires, fuel pressure regulator, vacuum module on side of intake, tps, coil, and even gutted cats. Didn't fix a thing. So what I did was bought a donar truck which was 91 single cab 2wd auto. That thing ran great on road nothing wrong with it that I could tell. I took motor and the wiring harness from driver side fire wall All the way around to the computer out and over and put in my truck. And I used my manual trans that was on my 2.9. AND still the same exact problem occurs with the 4.0 that I had with 2.9. the only reason for doing all that. So so I replaced o2 thinking that could be it and fuel filter again since that was all that was left from swap and still same thing haunting me. Please please any thing would help. I need this fixed. Thanks

 

[Fordfreak11]

I'm having ghost problem with 91 ranger 5 speed 4x4?

Hi new here but I need help. I'm pretty good at figuring stuff out but this one is beyond me. Ok I bought a 91 extended cab Ford ranger 2.9 5 speed 4x4 stock. When I would drive it it would have hesitation when you would give it to much gas while trying to get to speed and on hills would drop speed from 70 to 50 in no time. Like it had no power at all. If you let up off the gas a bit it would smooth out but not gain anymore power, but if I push the clutch in I could Rev it up with no problems at all. As soon as I would let clutch back out and give it a generous amount of gas to gain speed it would hesitate again. It was really hard to get up to speed to even shift if you give to much gas. I replaced fuel pump, fuel filter, plug ( motor craft), wires, fuel pressure regulator, vacuum module on side of intake, tps, coil, and even gutted cats. Didn't fix a thing. So what I did was bought a donar truck which was 91 single cab 2wd auto. That thing ran great on road nothing wrong with it that I could tell. I took motor and the wiring harness from driver side fire wall All the way around to the computer out and over and put in my truck. And I used my manual trans that was on my 2.9. AND still the same exact problem occurs with the 4.0 that I had with 2.9. the only reason for doing all that. So so I replaced o2 thinking that could be it and fuel filter again since that was all that was left from swap and still same thing haunting me. Please please any thing would help. I need this fixed. Thanks

 

[Fordfreak11]

4.0 wiring 2wd and 4x4 difference

I have a 91 extended cab 2.9 4x4 m5od. I have just recently swapped the 2.9 out with a 4.0. The donor truck was a 91 2wd 4.0 auto. I used the motor and engine harness out of the 2wd truck. Everything works great. I had to read the trends on here and found out how to wire the clutch pressure switch so that it still works like normal. The problem that I am having is that I can't seem to figure out how to get my push button 4x4 to work so I don't have 4x4. Can some one tell me what wires to need to wire in to get the 4x4 button to work. Or what is needed to have that working again!