2021 Ram 2500 6.4 Average Gas Mileage

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Fatbob Frank

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Engine
6.4L
My P.W has consistently averaged 15 mpgs a week running 87 no eth. all summer.
After switching to 87 w/10% eth ( cause it's .40/gal cheaper) it dropped to 14.5 mpgs.
Still not terrible for a big truck with a big motor and 35" mud terrain tires.
Now that cold weather has set in I'm only getting about 13 mpgs on average.
Combination of winter blended fuel and longer warm up times I suspect.
 

Raydulce

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Wisconsin
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2021
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5.7 e-Torque
My P.W has consistently averaged 15 mpgs a week running 87 no eth. all summer.
After switching to 87 w/10% eth ( cause it's .40/gal cheaper) it dropped to 14.5 mpgs.
Still not terrible for a big truck with a big motor and 35" mud terrain tires.
Now that cold weather has set in I'm only getting about 13 mpgs on average.
Combination of winter blended fuel and longer warm up times I suspect.
Thanks for adding this info Frank -- It's very helpful since I'm not far from you (similar weather, fuel, etc)!

As an FYI, I am averaging 14.7 mpg over the last 1 year-11k miles in an eTorque hybrid 1500 Ram Rebel. I run 87 octane with 10% ethanol at my dealer's recommendation.

Based on these numbers, I should have bought a Power Wagon! :) Thanks again!
 

Bearcatrp

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Hemi 6.4
My 2017 3/4 ton got 19 mpg on a long trip after 30,000 miles on it. Report back after 10,000 miles break in. My current 1 ton with a 6.4 is at 13 mpg average but only have 3300 miles on it. It will get better with mileage.
 

Fatbob Frank

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Unfortunately, the only time I get to take a trip in my PW I'm pulling a trailer so not sure what kind of MPGs it's capable of over distance.
I live in a valley so every night when leaving for work it's about a 2 mile climb( getting about 6 mpgs) before I hit the highway and actually get out of 4th gear...
 

Neil E

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Morganton, NC 28655
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2020
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6.4
On a 800 mile road trip, I averaged 20 mpg when the speed limit was less than 65 and I drove it. But when I somewhat kept up with traffic, it dropped to just under 18.
Normal day to day I average 13.5 mpg. 4.1 4WD CC 2020.
 

JE_75A_PW

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Alberta
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2021
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6.4L
21 PW w 4000 miles
Hwy
Picked it up from the dealer immediately drove 1200 miles. ( kept the msd off for "peace of mind " break in). Avg 15
Side note: drove couple hours at 90 mph. and it dropped to 13. ( I did expect this at 90)

In town - 11 ( all stock)
Installed 35's ( Toyo AT3) dropped to 8.5
Add in winter conditions with occasional 4x4 use, and I'm down to 7.5
( remote start is used, usually for one full cycle before driven)


I think the problem is the programming + VVT & the 8 speed
- final drive for the 8 speed is .64
- final drive for the 6 speed is .63
( could be a little off on this depending on year but its not a big enough gap to make a difference)

The truck seems to always be looking for the lowest RPM's in just about all scenarios where throttle position is under 75% ( guessing on % here but once you get so far into it, it will suddenly drop 3 gears and jump to 4000 rpm. You have to go with it, if not, it slams itself back into the gear you started with if you dont)
- So the transmission will always shift earlier and go to the gear, because its looking for the lower rpm and because it can ( 8 gears)
- it can do this because of the VVT. the engine can make power in that range now. However, this comes at a cost of course, and thats more fuel.

I just had a 2019 rebel and that was getting a disappointing 12 in town and 15 on hwy. This truck also has the same programming characteristics that the power wagon has.

Any thoughts ?
( I could be wrong, I was once before back in 87 so I guess it could happen again?)
 

turkeybird56

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I tell my prius friends I get two gallons to a mile
My 67 SS Impala with Big Block 396 and a 3 on tree got 10 mpg, LOL. I would always say: 10 gallons of gas and a quart of oil, LOL. Cannot comment on MPG since this is a 6.4 thread and I have the MY 19 5.7L non-torque.
 

NaCl342

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2021 Bighorn 4X4 Off Road Pkg
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6.4L Hemi
Plenty of responses here, only reason I am posting is because it seems our trucks are similar to compare. I also just took delivery of my 2021 Ram 2500 6.4L Off Road Pkg on July 5th this year. It was custom ordered via dealership and the only mod I have done so far is an S&B cold air intake and a Bak Flip Tonneau cover. I have 7000 miles on it to date and when I tow, it is a 30ft Dutchman Rubicon Toy Hauler with near 2K miles so far. Here are the numbers:
City 14 to 14.7
Hwy 17.5 to 18.2 (recent trip nonstop from gas station to station, Romulus MI to Grayling MI 18.2 mpg avg)
Towing 8.5 to 9 mpg
 
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Dean2

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2021 2500
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Small update. At 11,000 Klms I have recorded every tank of gas that has gone into my 2021 Laramie Crew Cab Long Box, 2500 with 3.73 gears. Almost all of the miles are on 87 Octane gas which has about 10% ethanol in it. The higher octane did not give enough better mileage to warrant the extra cost.

My all in, hand calculated average is 15.4 mpg. Lowest full tank was 10.3 mpg, highest was 18.9. I did hit an EVIC, whioch reads within .1 to .4 of hand calculated most of the time, rated 22.2 mpg for a 500 KLM stretch on part of one tank, but the rest of the way waz into a huge headwind and dropped the overall average for the full tank fill. Mileage is about 50% highway rest, hunting and around town. This is a significant improvement from my V10.
 
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OLEJOE

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N. La
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2022
Engine
6.7 CTD
Run your truck over a scale and weigh it. I weighed mine and it weighs 7800 lbs. with only my self and a full tank of gas. It takes a lot of energy to get that rolling. Add taller than stock tires and it takes more. Stop and go driving kills fuel mileage on these vehicles. Remote start is zero mpg.
 

thefiddler

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Iowa
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2017 Ram 1500 Laramie
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Hemi 5.7
Damn this is depressing. I have a 2017 RAM 1500 with a 4" lift and 35's and never see above 14mpg on the highway, 12 in town and 8-9 towing. This is with the 3.92 rear end as well. Apparently, I need to look into a 2500 with the 6.4. I love diesels but just dont want to deal with the egr and def issues as I don't do a lot of long distance routes...yet.
 
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