2021 Ram 3500 Limited Dually

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

RamGuy110

Senior Member
Joined
Sep 24, 2017
Posts
176
Reaction score
56
Ram Year
2022 Ram 2500
Engine
6.4 Hemi
Hello!

I recently picked up a 2021 Limited dually. It has the 68rfe and 4.10s. While, I'm pleased with the towing performance of the 4.10s, I wouldn't have ordered it with those, but since the night edition limited dually Rams are so hard to find, I took what I could get.

At 1600 miles on it so far, the fuel economy is quite bad compared to the 2021 dually 68rfe rental that I had from enterprise. Granted that truck had about 6k on it and was a 3.73. I wouldn't think the 4.10s would be much worse than a 3.73 or am I wrong?

I figured 1 mpg less once broken in.

I know adding larger diameter tires will bring down the gear ratio, but will that help with fuel mileage? Sorry probably a dumb question. 235/80/17 are oem, so if I put on 20s and went 285/65/20 maybe?
 

Billet Bee

Senior Member
Joined
Jan 4, 2021
Posts
454
Reaction score
341
Location
South Dakota
Ram Year
2020
Engine
Cummins 6.7 HOHD
410 definitly helps the fuel bill dig into the pocket book. I had a 373 with rfe and was getting 20+ miles a gallon, now I've got the 410 with aisin and get 12 . But have tohave the big dog to haul the mother load, so furl be dam
 

SniperDroid

Senior Member
Military
Joined
Aug 30, 2020
Posts
1,269
Reaction score
4,190
Location
Eaton Township, Ohio
Ram Year
2019
Engine
6.4 Hemi
I've been researching you question expecting to place an order on a 2022... Yeah, 4.10 is going to SUCK on the fuel in a noticeable fashion over the 3.73. You just have to decide what you want, Power or one or two miles per gallon. Since I'll NEVER go Diesel again, (the first part of Diesel is DIE) the 4.10 looks better for some extra power. If we ever get a trailer over 10K dry, I may change my mind, but for now it may just be the 4.10.
 

Firebird

Senior Member
Joined
Jul 19, 2015
Posts
1,488
Reaction score
1,460
Ram Year
2019 Ram 2500
Engine
Hemi
I don't have a diesel, but do have 4.10 gears, and yes, there is a mileage penalty. My 3.73 geared 6.4 did roughly 1 to 1.5 mpg better, but my 4.10 gears drag the camper easier
 

Wickenburg Geezer

Junior Member
Joined
Aug 31, 2020
Posts
12
Reaction score
9
Location
Wickenburg, AZ
Ram Year
2020
Engine
Hemi
No disrespect intended... But if you can afford a 3500 Big Butt, mileage shouldn't be an issue. Tell folks the same when they ask what kind of mileage my 42' motor home gets. You bought it and anything you do to it will only marginally improve mpg.
 

MoparProud

Banned
Joined
May 7, 2021
Posts
107
Reaction score
64
Location
Colorado
Ram Year
2007
Engine
6.7
There is zero chance there is an 8 mpg penalty between 3.73 and 4.10. It just doesn’t happen. It’s amazing in this day and age folks either blatantly lie about mileage, or have no clue how to figure accurate mileage numbers....hell there are APPS for that!!! Bizarre.

The mileage penalty ain’t that much. Really it isn’t. 1.5-2mpg TOPS! Now if you step up to bigger, heavier tires, then that’s more rolling mass and an additional mileage penalty.
 

tjfdesmo

Senior Member
Joined
Apr 15, 2014
Posts
2,255
Reaction score
4,038
Location
AZ
There is about 200 RPM difference between 3.73 and 4.10. Not a huge difference in MPG.
 

tjfdesmo

Senior Member
Joined
Apr 15, 2014
Posts
2,255
Reaction score
4,038
Location
AZ
No disrespect intended... But if you can afford a 3500 Big Butt, mileage shouldn't be an issue. Tell folks the same when they ask what kind of mileage my 42' motor home gets. You bought it and anything you do to it will only marginally improve mpg.

Is there room enough in Wickenburg for two geezers???
 

Timsdually

Senior Member
Joined
Jan 8, 2019
Posts
617
Reaction score
405
Location
Jersey
Ram Year
2020
Engine
Cummins
I am getting 15-16 in my 4:10 HO Aisin dually. I am very happy with that.
Driving the same routes in a 6.0 silverado 3:73 gas and the max I could get was 12.9, and that was really paying attention to my driving habits.
As long as they keep making diesel, I'll keep buying.
 

Billet Bee

Senior Member
Joined
Jan 4, 2021
Posts
454
Reaction score
341
Location
South Dakota
Ram Year
2020
Engine
Cummins 6.7 HOHD
I am getting 15-16 in my 4:10 HO Aisin dually. I am very happy with that.
Driving the same routes in a 6.0 silverado 3:73 gas and the max I could get was 12.9, and that was really paying attention to my driving habits.
As long as they keep making diesel, I'll keep buying.
Wholly mackerel how do you do it, I'm lucky if I can get 12 mpg soft footing it. The funny thing is when I soft foot it for a tank full to make the fuel last than ill have to get on the interstate and romp on it and let it regenerate because i babied it. So it don't pay for me to try and conserve
 

Timsdually

Senior Member
Joined
Jan 8, 2019
Posts
617
Reaction score
405
Location
Jersey
Ram Year
2020
Engine
Cummins
My driving from job to job is mix of open country road with traffic lights and stop signs and highway with traffic lights.
The funny thing is there isn't a real change from that driving to open highway.
I posted on another thread on a trip I took to NY towing open car hauler. Mileage the same.
I don't featherfoot it either. I won't say I am a leadfoot. Somewhere in between.
 
OP
OP
RamGuy110

RamGuy110

Senior Member
Joined
Sep 24, 2017
Posts
176
Reaction score
56
Ram Year
2022 Ram 2500
Engine
6.4 Hemi
I was thinking about adding a slight level and doing 34s or 35s. I would go with a 1.75" Thuren coil and install Revel links in the rear to raise the rear 1/2" or a little more than that. I'd go 20" rims and either Ridge Grapplers or Open Country AT3s and would go 295/60/20, 295/65/20 or 35/11.5/20 for tire size. Some say this will help fuel economy by bringing the 4.10 down to either 3.84 or 3.72 or 3.73, but then others say it will make the fuel economy worse.
 

GB53

Junior Member
Joined
Feb 8, 2021
Posts
4
Reaction score
3
Location
Last Frontier
Ram Year
2021
Engine
6.7 CTD HO w/ CP ISB21
16~17 here with 3.73 HO Aisin dually
 

Staff online

Forum statistics

Threads
194,925
Posts
2,864,171
Members
155,296
Latest member
VLG6963
Top