So I think I got a little ahead of myself **NEED HELP***

[Buzzard]

So, I finally got a 4.0l out a 98 B4000 got the wiring harness and both computers ( one from the cowl and one from the passenger kick panel). I a Planning to swap my 2.9 out for the 4.0. Where my questions are is ,1 - will my fm-146 5spd trans bolt to this motor? 2 - will I need both computers for this swap? 3 - What wires will I need and not need from the wiring harness? 4 - is this even going to be a good 4.0 to use?

Now for the good, the 4.0 has time gears not timing belts so it’s a little bit more reliable ( so I’ve been told) the motor ran like a top when pull from the original truck. And it has 195k original miles, oil is super clean and filter had no metal chucks in it or junk built up in it either when I cut it open.

This will be the first time I’ve ever done a motor swap on my own, any help, advice and or knowledge is very welcome and appreciated!

I’ll add a few pictures below of how Vegas sits now and of the motor I got!

Also if anyone would like to see and know more about Vegas I have a YouTube Channel called What_happens_in_Vegas88 recently started just for her. I’ll add the link below to! It gives a little insight to all the things I’ve done to her so far since I’ve owed the truck.

YouTube Link:

https://www.youtube.com/@What_happens_in_Vegas88

Quick description of Vegas:

• Black ~1988 Ford Ranger XLT 4x4 (Super Cab)
• 5spd FM-146 Transmission
• Borg Warner Transfer Case
• 4inch Rough Country Suspension Lift
• Sitting on Stock style 15x8 Aluminum Bullet Holes wrapped with 31x10.50R15.
• Original 2.9l V6 with 209k Miles

WANNA GO AHEAD AND SAY THANK YOU IN ADVANCE TO ANYONE THAT READS THIS AND LENDS SOME HELP!

 

[Curious Hound]

Someone else will chime in with more definitive info, I’m sure. But, from my understanding, you should use the engine wiring harness and pcm that belong to the 4.0l from the donor. The pcm is the computer that was in the cowl.

the other “computer” you saved is the GEM. That handles other vehicle stuff like courtesy lights and the battery saver relay and stuff like that. It’s more for controlling non-engine kinds of things.I don’t think you’ll need that.

I’ll call an expert @Ron D

 

[rubydist]

To answer your question "what wires do I need," you will need to get the wiring diagrams for your year (1988?) and for the 98 donor, and go through the connections from the dash to the engine bay and determine that. Since Ford likes to change a few things each year, there is not a reliable generic answer to that question.

You can use the transmission you have, but a M5OD-R1 would be a better choice imho.

 

[89RanBrII]

Check this out: 1st Gen 4.0 Swap

 

[lil_Blue_Ford]

Unfortunately, you set yourself up for a difficult swap. Nothing from the donor is ideal other than the block and heads.

It will bolt to the FM-146, but it may or may not survive behind the 4.0, the recommended transmission for a manual is a M5OD which was the manual transmission used behind the 4.0

The fuel system is incompatible, a 1988 used a lower pressure pump and a return line. Somewhere around 1998/9 they went to a higher pressure pump and eliminated the return line, so you either need to change the fuel system over or you need to replace the fuel rail and injectors. Of course, the computer you now have is only for the returnless system.

None of the wiring will be compatible, there’s going to be a ton of splicing.

A 98 will have an anti-theft as part of the computer, along with a module hidden in the dash and chip keys. If you didn’t get that stuff, then you will need to get it programmed out of the computer

 

[SenorNoob]

The FM-146 will bolt to the 4.0. Mine was supposedly rebuilt just before I got the truck. I used it and the stock 2.9 clutch and flywheel. The 4.0 revs quick with that little flywheel. The clutch slips before it has chance to do much damage. Acted kinda like a fuse for the transmission. I drove it that way for 7 years or so.