6.4l terrible mpg

[retired]

It should be noted that the 8spd trans made a big difference in the 6.4l efficiency...
Did the 2019 have that yet?

Yes

 

[Abiggunz]

Not to insult anyone but did you reflash the computer when you changed you tire size to 35s..if not your tire rotation is slower so the truck thinks your traveling less distance

 

[BigLazer4u]

Never got above 12 mpg in my 2019 power wagon with 35s. EVER!

 

[Rbertalotto]

I've had two 6.4L 2500...2018 with 3.73 gears and 6spd auto and now a 2021 with 4.10 gears and 8spd transmission. I've done extensive MPG test while on multi thousand mile trips. Both towing a 6K pound trailer and empty. Both trucks got 17 on the highway unloaded and 10 pulling the trailer. An extra 1/2-1 mpg while towing on flat land if I don't engage "Tow Haul"....There is ZERO difference with ECO engaged or selecting 6th or 8th gear to lock out ECO while empty. Put a canoe on the top of the trucks while towing the trailer and MPG goes up nearly a MPG!
63MPH is best speed towing and 70MPG returns best MPG when not towing.
I wrote a whole article about this here:

RAM 2500 6.4L HEMI MPG Observations | RVB Precision

Before we start, this will not be a doctoral thesis on calculating MPG with a modern internal combustion engine…….Just a bunch of simple observations. So before you Rocket Scientists, Geeks and Forum Experts start taking me to task for this not being “scientific”……You can stop reading...

rvbprecision.com

 

[Rbertalotto]

BTW...My truck was in service for 16 weeks waiting for warantee parts...But that's a whole other story. I borrowed a friends brand new (4000 miles) 1500 with V6/ETorque. I put about 800 pounds of stuff in the bed and drove from Massachusetts to GA, then to PA, Upstate NY and back to MA...all at 70-75MPH.......I averaged 23MPG!!!! I couldn't believe it. I hand calculated a few times and the trucks MPG computer was 100% accurate. And that truck had balls of power. Loved that truck!

 

[Wanted33]

A big truck with a big engine, low gearing, and 35's equals crappy gas mileage. I don't know what the standard size wheels/tires would be for your turck, but going back to those should help a little. Those 35's with the wheels added are a lot of weight.

BTW, you won't see any appreciable difference even of the MDS is working. IMHO that's just a gimick to get the truck owner a thimble full more gas out of a tank of gas, but spread across the number of trucks Ram sells it helps get them close enough to the CAFE numbers to make the Gubment stooges happy. I've only had my Ram for 10 days, but I have already developed the habit of canceling that crap out the minute I'm on the road.

 

[fordram guy]

Well guys I have two ram 2500 one is a 19, and the other is a 20 and the mpg between them is so far different. My 19 average is 14.5. My 20 gets 15.5 they both ride different as well. We took the 20 on a trip empty and got 21 mpgs no ****. Empty on the 19 the best I can get is 18.5. Now I have no clue why this is but I do not complain much it is a heavy duty truck. When we pull out three horse living quarters horse trailer which is heavy might say at with horses it’s around 19k we still do better than 9mpg, we sit around 11

 

[Timmerduder]

I have a 21 total stock power wagon and average about 12.5 between City and highway driving. I drive about half and half. I also tow a 26 ft camp trailer and get anywhere from 9 to 11 MPG there and if I'm on a total road trip I get about 15.5. now I do have the ram boxes and their full most of the time as well as a roll-up bed liner and usually two people.

 

[Maui Time]

I have a 2022 PW, 6.4 w/ 4.10's. I average about 16-17 on flat highway at about 65mph. Towing around 8k lbs I get about 10.

 

[Gazoo]

Not a power wagon, but I have a 2022 2500 6.4L GAS: I have NEVER, EVER, EVER gotten above 12.5 mpg. I reset every tank, I average 8.9 to 9.4. On highway I get 11. I just towed 7k# travel trailer 400 miles. Got 9.1 highway (plus thru mountains).

im waiting for a magical post where someone says, “just got back from dealer, they Re flashed my computer and now I get 20 mpg“. Ha! FYI, 6k miles on it so far.

 

[pjtj2k]

I have 2500 6.4 with 4:10. I get 17-18 with cruise on 70. When I'm towing I get 11mpg average. My truck is all stock.

 

[Scott DeRosa]

I have a 2016 Power Wagon w/6.4L engine. I get 10-11 mpg on local roads and get a much as 15-16 on highway running between 60-80 mph (from PA to Jersey shore). My truck has stock tires and only 18k miles. I have put fuel system cleaner/octane buster in raising the regular gas to 93 octane and that help increase mpg a little with out the high price of the gas.

Also I bought my truck new from the dealer and on the window tag under mpg was N/A, jokingly I said to my wife MPG-N/A I guess that means not a lot.....

 

[Udy2554]

My ‘18 PowerWagon on 35” Yokohama Geolander X-MTs definitely hurts at the pump! In 29,000 miles, I’ve had 6 tanks over 10mpg, one more over 11mpg, and one more over…gasp…12mpg! Pulling my toyhauler and gear(8500lbs?), 6.5+/-! The few times pulling the toyhauler has averaged a hair over $1/mile!

Not complaining…love driving it, wheeling it, and hauling with it!

 

[DrTron]

Also I bought my truck new from the dealer and on the window tag under mpg was N/A, jokingly I said to my wife MPG-N/A I guess that means not a lot.....

I think that's true for any HD truck as manufacturers are not required to supply economy numbers for those. So they don't.

 

[Ratman6161]

I have 2500 6.4 with 4:10. I get 17-18 with cruise on 70. When I'm towing I get 11mpg average. My truck is all stock.

What are you to2ing when you get 11 MPG? I've also got the 6.4 + 4.10 and pulling my 7600 pounds loaded travel trailer I'm lucky to get 8. I once got 9.6 with a strong tailwind and less than 7 in hilly areas or with headwinds. I'm not complaining though. I knew what I was getting when I saved $9500 compared to diesel and $1 a gallon lower fuel price :;

 

[dhay13]

I don't have a Power Wagon but do have a 2500 with 6.4 and 4.10's. I average 12.0 overall and about 16 to 17 on the highway but at 70 with 35's I could see it being lower. Mine is 100% stock with factory tires.
Wait till others with a Power Wagon chime in

oh..and I ALWAYS have MDS turned off. If towing I have it in tow/haul mode so that disables it and if not towing I manually put it into 6th gear and that disables the MDS also. I am also very easy on the gas pedal

 

[bcbouy]

Ram doesn't publish pw mpg numbers I don't think any hd trucks do

who said anything about ram?

 

[Chap]

I have a 2019 PW 6.4, 4.10 gears, Gibson exhaust, 35's, I get 9.5 mpg around town, 12mpg on the highway if im lucky.

 

[Chap]

Plus the must have pedal commander.

 

[JetDoc]

If you want good mileage and towing capacity, buy a diesel. My Ram 1500 4x4 EcoDiesel has 3.55 gears and gets 24 MPG in mixed city and highway driving. About 16 MPG when towing a 7500 lb camper trailer.