2017 3500 Heavy Duty poor fuel mileage

[Rsuarez]

Hello everyone,

I'm new to the group. I recently purchased a 2017 Ram 3500 Heavy Duty, automatic, crew cab, 8ft bed,srw, 4x4 with the 6.7 Cummins. I mostly use it to tow my boat. So during the week it's always running empty. My fuel mileage is around 10.5 to 11.3. When I tow the boat it drop very little to around 8.9 to 9.2 the boat with trailer is around 10k.

I'm in Florida so there are no hills or mountains or winter fuel issuses.

Is this the normal fuel mileage? Also the truck only has 75k miles on it.

Thank for the help.

 

[WY-Dave]

I's say something is wrong to start with. My '18 2500 auto, CC, 6ft, 4x4 6.7CTD daily driver gets mpgs in the 16s. This is with rolling hills and more than not headwinds. It has 3.42 gears.
BTW Title says 3500 but in the post you say 2500

 

[Rsuarez]

Thanks I just changed to 3500. My old one was a 2500. Just still used to say 2500.

 

[OrganizedChaos]

Just got my 2017 3500 with CTD and have put about 400 miles on it. Evic shows 18.1 average over those miles. Have bigger tires and 70 on the speedo is actually 75 so thinking the evic might be close.

Sent from my Pixel 3 XL using Tapatalk

 

[Rsuarez]

My shows 10.2 as of today. With only having put about 1000 miles on since I got it. About 3 weeks ago.

 

[BubbaJo]

what gears are you running? when was the last time you changed your fuel filter? Have you tried filling up at a different station?

I have noticed in my small town, that fuel mileage will go up and down depending on what station i buy it from. Heck one station would even throw a SEL code on me when i got to around 1/2 tank. Stopped going there and saw my mileage go up a little and haven't had a light since.

 

[Rsuarez]

Have 3.73 gears. Only have had the truck about 3 weeks but yes have used different fuel stations. Milage has stayed the same.

When pulling the boat we travel about 300 miles each way. Gets down to about 9 - 9.5 with about 10k. This week has only gone upto 10.5 not hauling anything.

 

[MADDOG]

Something is wrong with the fuel system. I suspect it may be the fuel filters.

I looked at your engine designation on your profile and have a question.

What is a "Cummings" ?

 

[BubbaJo]

i forgot to ask that. When was the last time your fuel filter was changed? Air filter? what type of tires are you running? aggressive tread? are they pumped up all the way? (mine requires 70psi)

 

[18Aries]

I’m sure he meant Cummins

 

[Smokeybear01]

I have an older 5.9L but my first thought was fuel filters. Don't wait for the dash to tell you there's water in your filter. I see so many diesels going down the road that you can just tell they're filters are gunked up. Good luck,

I should add, this is not my first diesel and I've worked around them a lot. FWIW

 

[dputnam01]

I've got 43k miles on my 2018. I also average about 16 mpg between highway and local mountains. I keep it above 1/2 full fuel, and have performed maintenance (fuel filters, etc) per schedule. I don't tow very often, but typically cart around 400 lbs of dogs

 

[jejb]

I've got 43k miles on my 2018. I also average about 16 mpg between highway and local mountains. I keep it above 1/2 full fuel, and have performed maintenance (fuel filters, etc) per schedule. I don't tow very often, but typically cart around 400 lbs of dogs

18 what exactly? 3500 dually? What gears?

 

[ACJCF2]

My 2018 3500HD 6.7L, CC, DRW, 4x4, 3.73 gears with 20k miles averages 18.1 mpg ± empty and 9.5 -10 mpg pulling our 17,000# fifth wheel. As my buddy with an '09 Chevy 3500 told me, "you didn't buy your truck mileage, you bought it to work." That said, I'd have a chat with your dealer.

 

[ppine]

Change all of your filters. Lighten up your right foot and get back to us.