Hi, it's been a while since I've been on here, but a while back I swapped out my 3.9L for a 5.2L, and have had the V6 sitting in my garage doing nothing. I want to get a smaller RWD Dakota to put it in, for more of a "fun" car. I found a Dakota for sale near me that I believe to be a 1994, with a 2.5L that doesn't run, and 5 speed manual. How difficult is it to swap the 4 banger for the V6? I'm not concerned about wiring, I have that figured out, but regarding motor mounts, bellhousing, etc. Will a lot need to be changed? I'd like to use the current transmission that's in there, if possible. Any thoughts are appreciated. Thanks.

 

The frame horns for the motor mounts will need to be swapped to the V6/V8 horns; those will probably have to come from the wrecking yard.

The 1994 I4 was the Chrysler, but I can't find anything on its bell housing pattern; it may, or may not, match the V6. If not - at least the transmission should be a AX-15, which at least has a separate bell housing - which isn't listed in the parts diagrams I have, alas. But SHOULD be available. According to the FSM, the AX-15 was used behind both the I4 and the V6.

Exhaust and wiring will be the biggest problem, I bet. For those it'll be best to find a donor. For all but the ECU, you can use either a V6 or V8 donor; for that, you'll want a V6 ECU. (Pro tip. Find a V8 donor for all of it, engine wiring and engine bay wiring. That way when you decide to drop a 5.2 or 5.9 into THAT truck, it'll be prewired.

Donor can also donate the frame horns for the motor mounts.

RwP

 

Alright great. I'll look into it if I get it, which I probably will at this point. Didn't know what transmission it had, but I'm glad to hear that it's probably an ax-15. I already have a V6 ECM, two of them actually, and I'll most likely make my own harness as well. Thanks for the info

 

Swap it for a 5.9L.

 

As some have already said, the V6 doesn't really warrant the work, it has less power and hardly justifies itself based on fuel efficiency. I've only ever been able to get close to 22 out of mine and I drive pretty conservatively. Had a 94 B250 with 5.2 and AOD it could get 20 so perhaps it is the case that the V6 ends up being the short end of the stick. Personally I don't like AT and think the V6 might do better with MT but it doesn't have much low end grunt and if you're on anything other than a true flat it will come out of OD at the slightest provocation. And using cruise on anything but a flat is a completely frustrating situation IMO.

I know you have a V6 you would like to use but I'm suggesting that it's not worth it to go to a lot of effort just to install that engine in something, that is unless the something is free. As for the size situation it is true that before the AMC 2.5L engine the 4 cylinder was only installed in the regular cab short beds, but I'm not sure it's going to make all that much difference if you take that 4 cylinder 94 and convert to V6, that is unless you're set on doing that.

Here's how the weights break down, I trust that this is fairly accurate although I'm sure there's some rounding:

1996
base truck (reg cab / short bed) 4 cyl = 3042 lbs
4x4 +360 lbs
V6 + 250
V8 + 360
8' bed + 100
extended cab + 230

If you have the time and want to do it that's awesome, if it were me I wouldn't bother with it just for the 3.9L V6, I'd personally like to pull mine and install a 2.0L turbo diesel or similar, at least there would be some benefit to having gone through all that work.

Steve

 

I think I have mentioned this before but I have the 3.9 and If I knew then what I know now I would have saved myself the 4 grand I spent making this $900 truck run and just got myself a V8 crate motor or even a running junk yard V8. It would have been cheaper and I'd be getting better MPG's and more power. My 95 Pathfinder v6 had more power and better MPG's. That was the basis of my choice to try to make this one run better.
if you don't haul stuff and don't really need the power of a V8 I'd advise a rebuild or a crate motor of the exact same type.
Edit: I have been thinking that if I do eventually choose to get a V8 I would put the V6 into my Ram 50. It would probably get better MPG's because the truck is so much lighter. I get 19 or 20 MPG on all hwy trips. In town the best I can do is 15.47. It's been 13 and 14 more often than not.