My son recently totaled my '94 5.2 auto 4x4 Dakota ext cab. Really want another Dakota, had it for 14 years. Never did any serious off roading or towing, mostly highway driving, use the 4wd mostly for snow & ice. My question is how much of a power drop off will I see with the 3.9? What kind of mileage do you get with the 3.9? I averaged about 14.5 with my 5.2. Thanks for any input.

 

I average between 17 and 18mpg. I'd rather have a V8.

 

I get about 15 driving around town with my 1989 3.9L, manual, 4x4. When I drove it from PA to AZ I was getting about 20-21mpg doing between 65-70mph. I would also like a V8. From what I have heard on here that most people that do the V8 swap only loose 1 mpg.

 

IMO, the v6 is inadequate for towing, or 4wd, and should get much better mpg.
My 95 2wd with 5.2 and auto trans and 3.55 gears got consistent 20 plus mpg on freeway trips. We used it a lot going from Phoenix, AZ to Logan, UT and back several times a year.

I suspect the replacement v6 and v8 are much the same as those used from 92 to 2000 or so....

 

There is not a lot of power with that v6...when I had mine i had to constantly floor it to go up hills. You'll regret not getting the v8

 

My '95 5.2L 5 speed when it was on 31.5 inch tires with 3.55 gears got a consistent 15.5 mpg all over driving (city and hwy)... and yes, the speedometer/odometer/trip meter was corrected for the tire size. The 5.2 has plenty of power for this truck! I pulled a 5500 lb trailer and the truck had no problem going 75 mph doing it!

 

I drove an 89 Dak 2WD with 6-banger for about five years, '90-'95, and it was kinda doggy with the throttle body injection. Never checked the mpg, cause gas was cheap...and never towed with it. 20 years later, I'm driving a 93 Dak LE cab 4WD with 5.2 V8, fuel injected, and get 14 mpg in town and 17-19 mpg down the road at 68 mph in OD. Love the auto tranny, and the performance of the little V8...smooth running at all speeds and power whenever you need it...just put your right foot to work a little.

 

the 3.9 is way underpowered for a 4x4, especially the pre magnums like in my 89. i get 15 highway in the summer, come winter it drops to around 10 to 11 with some 4x4 use for snow. for towing its ridiculous even on the slightest hill, flat roads are fine just dont expect to pass even a bread truck

 

I had a 94 3.9 for a year and got rid of it for a 5.2.

Even just throwing a snowmobile in the box was too much for it. Depends on what you are going to use it for, but I have not seen the 6's get much better mileage than the 8's.

and hello again fellow Dakotian!

 

haha i know this feeling my 3.9 is the same way