I did not realize the V6 Dakota's might drink that much fuel. I thought those trucks typically got closer to 20 mpg. It sounds like the mileage can vary considerably.

My D150 only got 10 mpg on the one tank I checked. That tank was used for mostly short trips with plenty of starting, stopping and some idling time. Often the choke probably never even opened. I was not expecting it to be very good. It's a typical 318 / automatic truck with 2.94 gears. It escaped from the factory without the "lean burn" system or the lock-up torque converter. When it is driven on longer trips it will hopefully use a little less fuel. Obviously, it will never be an economy vehicle.

The D and W series trucks I've driven have typically been 3/4 ton, 4x4's that got 10-12 mpg. The EPA rates my current truck at either 12 or 14 mpg. I have not found what made the difference in the rating. Perhaps it was the axle ratio, but it could depend on whether or not the truck had the "lean burn" system. The 2.71(?) axle ratio was standard. The 2.94 and 3.21 ratios were optional.

my last 83 D 250 (318, 727, 3.55) got me 13 on a "bad" day in town. usually closer to 15.
my 88 D100 (318 TBI, shortbed, changed from 904 to 518 myself in effort to increase MPG, wasted effort) got me 10 on a GOOD day, 12 on the highway with a 60MPH tailwind. worst MPG truck I have ever owned.

my 81 W150 (318, factory TQ, 727, 3.21 gearing, 33" tires, longbed reg cab) was surprisingly fantastic on gas, that thing would get me 21 consistently on the highway, 16ish in town.

my 87 B 250 window van (318, last year for carb, lean burn, 904) would get me 21 on the road when not running AC, 19-1/2 when I did, yet my Dad's twin (only difference was his was '86) would get 13 no matter what.

even my 78 D300 (360, granny gear 1st, unknown gear rear, dually) was better on fuel than my 88. Not by much but it was/ and considering it weighed nearly double what the 88 did was surprising to me.


I have also had a 90 longbed Dakota 2wd (pre magnum V6) quite consistent 16 in combo driving, 20 on the road)
best Dakota for MPG was my 93 318 club cab, converted to 5 speed by me, never got worse than 18.

94 reg cab/shortbed 3.9, usually 14-15, best of 17.
my 99 club cab (same engine) is pretty much 17 no matter what/ other than when pulling my popup, when it says "HELP ME!!!!" I wouldn't want to take that one camping in the hills/mountains..... good thing I live in the flatlands.....does OK when not towing as a daily, still a bit weak on power (in my opinion) in that instance.

Gas mileage is a funny thing. I can get consistently better gas mileage then my wife ever gets, driving the same vehicle, and I usually don't try to get the best gas mileage. My right foot appears to be quite heavy at times (OK, often times..)

In the early years of EPA mileage numbers, I believe the EPA was pretty generous with the numbers they handed out. Don't know many people that ever got within 2-3 mpg of what the EPA said something would get. I believe originally, the EPA mileage numbers were intended to be used for comparison with similar vehicles. You could look at all the truck numbers for a specific year and get an idea how the different trucks would compare. I also don't believe the EPA numbers were based on any scientific test, but more on lab tests.
I think the more recent numbers may be closer to reality, but maybe not. Gene

My 95 short bed auto averaged 18-19 mpg the entire 8 years I drove it- ( had 82 K when bought it- 96 K when I sold it= sold it last summer but shouldn't have- Just used it to haul bicycle around mostly/ Came close to 20 mpg a couple times

You all know those highway numbers are done at a constant 45 MPH on rollers right?

wow, you only put 14k miles on it in 8 years? I bought my 99 Dakota back on 6/1 of this year, and already have more than 14k miles on it since I got it.... and that's even with me and the wife switching off (we have 4 vehicles among us, so 2 are sitting at any given time) AND with the 99 sitting 2 weeks, while I collected parts and did the repairs from Bambi's banzai suicide jaunt out in front of me on a country road, a whole 10 days after I bought it....

Thank you again everyone. Gas mileage isn't a top consideration. I figure if I can get over 11-12 mpg average I'm good. The only thing that I see with the D-Series trucks is some parts availability. For example no one has a brake booster and so now it has to be sent out for a rebuild service. The other thing is control arms. Most people want to lower their trucks and I don't. It's getting harder to find factory control arms brand new. The WSD stuff isn't that great of quality from what I understand. The other thing is some of the emergency brake stuff isn't available.

Regarding the body. The only way I would buy a truck is from the west or somewhere in the south. Prefer the west however. I'm hoping not to put a ton of miles on the truck anyway. I did consider a 3.9 Dakota but, I'm not sure. Anyways, time will tell what I end up with. Thank you for the thoughts and feedback. If you have anything else to add let me know. Thank you.

Some of these parts are the ones I watch for NOS. As far as emergency/parking brake stuff for D/W trucks, I just replaced all of mine on my 1979 Power Wagon, and it was all available on Rockauto. www.rockauto.com/en/catalog/dodge,1979,w150+pickup,5.9l+360cid+v8,1099841,brake+&+wheel+hub,parking+brake+cable,1696

Gas mileage has not bothered me one bit. I don't drive it daily, but frequently. I don't notice it to be sucking up the gas so much that it's ridiculous. I love driving the truck. It's tight, and a pleasure drive.

P.S. I just checked O'reilly Auto Parts and online shows they have remanufactured Power Brake Boosters for 70's D/W trucks. https://www.oreillyauto.com/detail/...p-4wd?q=power+brake+booster&pos=1#rr

Hello. What I mean is things like some of the emergency cable brackets that attach to the frame. I don't have part numbers on hand. The brake booster shows available but, I think some other guys said it wasn't available. As I said factory control arms are getting scarce but, hopefully someone will reproduce quality ones eventually. Thank you again though.

I just ordered a Reman'ed 1979 D150 brake booster (2 bolt master) from RockAuto. Its like $72 plus $16 core.
They have the 4 bolt master ones too.

Wasn't my daily ride- used for occasional- sod, branches, etc- Was pretty much used to keep my bicycle in and haul to start of rides..... trying to live for ever- at least another year----

Fortunately, booster is available as you know now

The parking brake mounting brackets probably won't ever fail you. But you may still find those in a yard or used on ebay or here. Those were the only things that were still good on mine. The cables go but the brackets are thick metal with only surface rust.

Thank you. I see RockAuto is out of stock on the boosters now for both a '79 D100 or D150. That's okay though. Thank you again everyone and take care.

Opps. I just bought one for my 78 LRT. Going from 4 bolt master to 2 bolt. My OEM bladder is bad.

My LRT will never be a #1 show truck, it has a 1978 'W' 360 block in it so not numbers matching.

So I do have a smaller diameter but a bit deeper Vac booster from a 1985 OMNI that has the same firewall bolt sizes I think. I may just use that OMNI unit and sell this Reman'd one.