Got the computer replaced and the truck (96 3.9 Ext Cab 4x4, Automatic) is running great other than the oil smoke coming from the tail pipe now.

Looks like the oil rings are shot, with just over 50k miles on the motor. So here is where I am... rebuild the lower end, change a few things, ie the Cam, rocker arms. Or do I just say screw the 3.9 and drop a 5.2 in her.

The question is how much do I have to change over when moving to the 318? And does the cost worth it?

 

If the cost is worth it or not is up to you. See if you can find a dakota with a 5.2 at a dealer and drive it. That would give you an idea if it feels like something you want or not.

There are several swap threads here available in the faq, or by search. You will most likely want a new transmission from behind a v8 as well as the motor/harness changes. THats covered in those threads.

 

If you have the time I would say do the V8 swap. Check the FAQ2 for links to several posts on it with full details.

 

I also agree do a v8 swap. You're talking about just a little worse gas milage for a huge power increase. The two big things you need to worry about are wiring in the extra 2 fuel injectors (or just getting a v8 wiring harness), and either building up your 42rh transmission with performance clutches and a shift kit or finding a 46rh. Everything else is plug and play.

 

V-8 swap.
The V-8 usually gets about the same MPG as the V-6, but, like 95_318SLT said, much more power!
As 95_318SLT also said, you will need a V8 computer, and either (A) the V8 engine wiring harness or (B) just run the wires to the "extra" two injectors.
As far as the transmission, you *can* stick with the automatic running behind the V6 (42RE, not 42RH, since you have a 1996) and it will work as long as you don't plan on doing much upgrades and getting on it all the time (a Gen 2 owner is running the V6 trans behind the V8). Ideally, since you'll have everything ripped out if you swap to a V8, you should just swap to the 46RE.

 

Went out looking on the web and found a 95 Dakota motor and trans for 1400 close by the house. I called and the guy saids it runs with 114k, so look like I have a trip to take.

Thanks for the info. Will post what I find.

 

Just a little note:
The wiring harness is different for 1995 and 1996. 1996 implemented OBDII.

For the COMPUTER:
1995- one 60-pin connector.
1996- three 32-pin connectors