Poor fuel mileage highway

[bigoldthor]

My first day trip last weekend (all interstate) yielded 18.5 mpg (per truck computer) on a round trip from Evansville, IN to Simpsonville, KY and back. Probably 250 miles total. Gently rolling hills, good weather, not much wind, set cruise at 75 mph most of the time, tires set at 40psi cold. 3.21 rear end, 20" stock wheels and stock BFG tires, truck only has around 1000 miles on it, so hardly broken in yet. Not great but I can live with it. My all-around combo 50% city/highway driving is around 16-16.5 mpg. I drive pretty normally...not overly aggressive but not like I have an egg between my foot and the gas pedal.

I did some calculations based on my 2017 F150 with 3.5 EcoBoost which was averaging around 17-17.5 mpg. If the delta is 2mpg (15.5 vs 17.5, worst case scenario I believe), I drive 15k miles per year, and gas averages $2.50/gal, it would cost me $276 per year more than the Ford. If it's only 16.5 vs 17.5, it's $130. So I'm not gonna sweat it and just enjoy the truck.

 

[big al]

2019 5.7 hemi with 3.92,e torque. Rated at 17-22. Highway mileage is only around 16-17 and that’s driving speed limit, not passing etc. Truck only has 1300 miles on it. However it’s getting better mileage in town 17 mph, that etorque really seems to help in town? Just wondering if others have had same problem. Maybe better once I get a few more miles put on it? I was hoping for 21 at least.

? Give it more time to break in...

 

[buffalobill]

just got back from a 830 mile round trip to Albuquerque . I averaged 19.5 mpg running 75 -77 mph , all interstate . 3.92 gears , couldn't be happier .

 

[Hydroblueguy]

just got back from a 830 mile round trip to Albuquerque . I averaged 19.5 mpg running 75 -77 mph , all interstate . 3.92 gears , couldn't be happier .

How many miles are on your truck now?

 

[maddog49]

Mileage seems to go up dramatically if your not at sea level or drive on flat land. We averaged 17.5 on a 3000 mile road trip from Il to fl recently with a full bed and 5 people in the cab running 74-80ish on the highway. While not amazing it was decent. Truck had 17k miles at the start of the trip. Mileage has gotten better after the first 10k.

 

[snj1013]

I have a 4x2 Hemi, 3.21 rear axle and get around 17-18mpg in suburban driving, 20-21mpg at 75-80 on the highway. Those numbers will likely go up 1-2mpg when we get back to summer blend gasoline.

 

[69385vette]

I took a 750 mile trip from Austin to Birmingham. According to the trip meter, I averaged 21.3 mpg. Mostly on I20 running 70. I am very pleased with the truck.

 

[Tuan2766]

5.2k miles, got 4x4, 3.92 rear, & etorque. I drive from a city apartment to suburb area for work. Approximately 75% of my driving is on the freeway and the rest is city. I drive with a light foot, and only gas it up when needed. I am currently averaging 16.3 mpg combined and have not reset the mpg calculator. I took a mini road trip once traveling on the freeway and got 18mpg combined. Then I took off 3 days and stayed home, drove around the city for 3 days and total mpg dropped to 14.7. Feel like city mpg is 14 mpg or below and highway hovers around 20 mpg. Etorque seems like a gimmick tbh, minimal gains, it just happened to be on the truck I purchased but didn't really care if I had it or not. It will not stay on if the a/c is blasting and therefore kinda pointless in Texas summers.

 

[RickWaz]

I'm getting 15.8 - 16.5 w/ 98% highway driving and I have ~ 4,500 miles. I only use 89 octane.

 

[2019REBEL]

12.5mpg commute to work at 6mph, 14.7mpg I-95 at 80mph. Not much different from my 235HP `97 Expedition 5.4 triton...

Must take you forever to get to work at 6mph

 

[LimitedDRP23]

16.2 mpg so far on mine.... 4x4, 3.92, running mixture of 87 & 89, switching to all 89 moving forward. I figure 65% freeway, 35% city

 

[kapinallinen2]

Must take you forever to get to work at 6mph

It is a bumper to bumper PITA on most days.

 

[Narg]

I recall a thread on this for a different vehicle I bought a while back. Seems most engines start to improve efficiency between 2K and 4K miles. FWIW.

 

[4timeRamOwner]

2019 5.7 hemi with 3.92,e torque. Rated at 17-22. Highway mileage is only around 16-17 and that’s driving speed limit, not passing etc. Truck only has 1300 miles on it. However it’s getting better mileage in town 17 mph, that etorque really seems to help in town? Just wondering if others have had same problem. Maybe better once I get a few more miles put on it? I was hoping for 21 at least.

Same problem here. Trust me, it won't get any better. If anything, your city mileage is going to drop off. I can't get better than 13.25mpg city in mine with the eTorque. Time to complain to your dealer. We need a grass roots effort to fight back against this issue. Call Mike at FCA 866-932-3873 extension 3020888 and complain to him directly. He's my case manager and he says he has NEVER heard of this issue, yet hundreds have complained on this forum.

 

[Hydroblueguy]

Same problem here. Trust me, it won't get any better. If anything, your city mileage is going to drop off. I can't get better than 13.25mpg city in mine with the eTorque. Time to complain to your dealer. We need a grass roots effort to fight back against this issue. Call Mike at FCA 866-932-3873 extension 3020888 and complain to him directly. He's my case manager and he says he has NEVER heard of this issue, yet hundreds have complained on this forum.

I’m getting 17 in town but only 17-17.5 highway with the e torque. Think mine might be related to tires being out of balance. It will not hold balance for more than a few hundred miles. Been balanced twice already before 1700 miles. No off road driving!

 

[TheRealCanadier]

Generally how long does it take to break the engine in to the point where the fuel economy is at it's best? My 2020 Ram 5.7L, 3.21 only has 900km (559miles) and at highway speeds sits at 12-13/100km (18-19mpg) This is with winter tires on also. Just curious as to what I should expect it to get down to and a rough estimate as to when it will settle more.

 

[TheRealCanadier]

Also, does MDS only kick in below 80kph? I never get into eco mode on the highway.

 

[gtxdana]

My last tank was good for 12.5 MPG. Mostly in town, but not stuck for hours idling in traffic on that tank, and I pretty much baby the truck. On one tank, with probably 60% city/40% hwy, I got 13.5 MPG. I can't wait to see how bad the mileage is when towing my enclosed trailer at about 7500 pounds with this truck. Hemi/non E-torque/3.92

 

[Richard320]

Generally how long does it take to break the engine in to the point where the fuel economy is at it's best? My 2020 Ram 5.7L, 3.21 only has 900km (559miles) and at highway speeds sits at 12-13/100km (18-19mpg) This is with winter tires on also. Just curious as to what I should expect it to get down to and a rough estimate as to when it will settle more.

Mine was about 4000 miles.

I have seen the ECO light on as high as 72 mph, but that was on a slight downgrade. Generally it won't work much above 60 mph.

 

[Jako]

Generally how long does it take to break the engine in to the point where the fuel economy is at it's best? My 2020 Ram 5.7L, 3.21 only has 900km (559miles) and at highway speeds sits at 12-13/100km (18-19mpg) This is with winter tires on also. Just curious as to what I should expect it to get down to and a rough estimate as to when it will settle more.

My truck had 14,523 miles when I started a 2201 mile trip. With 7 fill ups I have averaged 20.24 mpg. Most of the driving was on interstates I 95 and I 81 with 75 mph + or -. My mpg ranged from 18.77 to 24.21. I did get stuck in traffic a few times which crimped some of my mpg.

I tend to feel if I stuck at 65 or less mph or so and straight, flat roads I could get the 23-24 mpg.