Ram 2016 3500 6.7Cummings with 342 rear

[mwaroley]

Hello, I am considering buying a 2016 Ram with the 6.7 Cummings, 6 sp trans,however the truck has a 342 rear. talked with someone who owned one who said he was only getting 6mpg towing a 17K weighted trailer. I have a Keystone sprinter 5th wheel that weighs 12.5K ready for camping. Anyone with similar truck getting any better gas mileage? 6 seems awfully low

[chuckster57]

Welcome to the forum!!!

If your trailer is 5,000 pounds lighter, that will make a huge difference. Choosing the right gear in certain conditions will help too. 6 does seem low with 3:42 rear end, but he may have been lugging it a lot.

[JRTJH]

I've got a 2015 F250 6.7L (I know, entirely different engine) with a 3.31 ratio. I typically tow a 9500 lb fifth wheel, run in 5th gear at 1900 RPM or in 6th gear at 1700 RPM. Average about 10.5-11.5 MPG. If he's only getting 6MPG, he's either got something wrong with the truck, the emissions system or his trailer brakes/bearings. He should almost always get over 9MPG, even with a moderate headwind. Other's will chime in with more comments, but I'd say his experiences do not reflect the norms for RAM's diesel economy.

[mwaroley]

He also was towing to Sturgis ND from Fl. A lot of hills between here and there. While a lower geared rear would seem better for towing I cant believe it would cause that poor fuel mileage.

[gearhead]

I had that same truck previously. The RAM SRW diesel is, or was, only available with that rear end ratio. Our 5th is the same GVW..12,500#.
Like John said, you should get at least 9mpg. I usually got 10-12.
On relatively flat roads I used tow/haul and let the transmission shift when needed. In big hills I usually dropped the transmission down a gear. I never saw any high transmission temps or had any worries about that truck/5th combination.

[Frank G]

Same truck same year same configuration. Towing 13K according to "Fuelly" it gets 10.5 to 11.5 towing up and down I-75. Empty 21 to 22.5. Around town about 19+.

THEY ONLY COME WITH ONE GEAR RATO IN THE 2500, 3.42

A 17K trailer is total overload for that truck.

[notanlines]

Nope, something is wrong. Either his math, the emissions, the list could go on and on. We tow about 22K in triple tow mode and get 9.8 all the way from northern Wisconsin to Memphis, to south Florida. Average about 64 MPH. Worst we ever got was 8.2 in the monstrous head winds across South Dakota headed to Sturgis last August.

[rhagfo]

Hello, I am considering buying a 2016 Ram with the 6.7 Cummings, 6 sp trans,however the truck has a 342 rear. talked with someone who owned one who said he was only getting 6mpg towing a 17K weighted trailer. I have a Keystone sprinter 5th wheel that weighs 12.5K ready for camping. Anyone with similar truck getting any better gas mileage? 6 seems awfully low

Well we just found a 2016 Ram Laramie 3500 DRW with 3.73's and the Aisin. Now if your Ram has the Aisin then the 3.42's are not that bad as it has a lower 1st gear. I will say our old 2001 Ram 2500 CTD had 3.55's and a 5speed manual, and getting off the line was not the quickest with 12,500# in tow. The link below will provide a build sheet for the VIN you are looking and confirm if it has the 3.42's.

https://fcacommunity.force.com/RAM/s/equipment-listing

[gearhead]

To be clear I had a 2016 3500 (1 ton) Single Rear Wheel. I was within all capacity limits with the 5th. Only reason for the new dually is the loaded cabover was well over the SRW payload of 4217#.
edit add....the new RAM dually has 3.73 rear end. I can't tell too much difference but haven't towed the 5th much yet. Aisin transmission in both trucks.

[mwaroley]

Thanks for all the replies. If I get 10 to 12 towing I would be happy with that. I guess the thing to do is keep it under 70 on the inteerstates

[Frank G]

The 2016+ Ram 2500 and 3500 with the 68rfe 6 speed and the CTD all share the same platform with the 3.42 gears and 800 Ft Lb of torque Cummins Turbo Diesel. The Aisin 6 speed in the 3500 is married to a HO Cummins producing 925 Ft Lb of torque and a selection of gear ratios. These are two different platforms and should not be compared for fuel efficiencies. They both preform well within there design parameters.

[gearhead]

Depending on traffic, weather, type of road, my tires, etc., I usually drove just a little under the speed limit, especially a high limit...70mph+.
You'll get 10-12.