Bad fuel mileage 5.7 hemi

[jz5w63gwilli]

Anyone else getting less than 14mpg? My 4th gen got way better economy. I know it’s a truck and I don’t expect amazing economy, but i do expect to get what I got out of my 4th gen which was 16-17, and also does anyone have a vibration coming from the drivetrain when In 4wd hi or auto?

I don't get near the mileage on my 19 crew compared to my 14 quad. I have the same powertrain incl 3.92 axle. Have 7000 miles. ECO does not come on nearly as often. Is the weight of the crew vs quad the factor? Avg currently 12.8 vs 16 on the 14. Same area and style of drive.

 

[RichT]

for whatever reason, ECO comes on all the time now that I have the topper installed.

 

[Zeronet]

I don't get near the mileage on my 19 crew compared to my 14 quad. I have the same powertrain incl 3.92 axle. Have 7000 miles. ECO does not come on nearly as often. Is the weight of the crew vs quad the factor? Avg currently 12.8 vs 16 on the 14. Same area and style of drive.

According to fuelly.com the 2019 quad cabs are averaging 16mpg compared to 14.5 for the crew cabs. So yes, it appears that the crew cab does affect mpg to some extent.

 

[Barney556180]

for whatever reason, ECO comes on all the time now that I have the topper installed.

The cap improves the overall aerodynamics, so less wind resistance equals higher MPG.

 

[slimchance]

According to fuelly.com the 2019 quad cabs are averaging 16mpg compared to 14.5 for the crew cabs. So yes, it appears that the crew cab does affect mpg to some extent.

that makes no sense to me at all .. the overall length is about the same and the weight difference is minimual ... i think there are just more crew cabs in their sampling

The cap improves the overall aerodynamics, so less wind resistance equals higher MPG.

what about the 200 - 300 lb weight of the cap ... i have a cap ... the rear window and tail gate is always dirty because of the aerodnamics ??
the increase in mileage is centered around driving style IMHO

 

[Jwsmith]

that makes no sense to me at all .. the overall length is about the same and the weight difference is minimual ... i think there are just more crew cabs in their sampling


what about the 200 - 300 lb weight of the cap ... i have a cap ... the rear window and tail gate is always dirty because of the aerodnamics ??
the increase in mileage is centered around driving style IMHO

hi to

 

[Barney556180]

that makes no sense to me at all .. the overall length is about the same and the weight difference is minimual ... i think there are just more crew cabs in their sampling


what about the 200 - 300 lb weight of the cap ... i have a cap ... the rear window and tail gate is always dirty because of the aerodnamics ??
the increase in mileage is centered around driving style IMHO

I agree driving style does have most influence on MPG.

My understanding is that in spite of the added weight, a cap does smooth air flow over the vehicle compared to an open bed. Even a tonneau cover is an improvement overall.

The dirty rear is evidence of back draft which, while still turbulent, improves slipperiness compared to the bed cavity and tailgate “sail” catching the air.

 

[Jwsmith]

View attachment 24441View attachment 24442 hi toView attachment 24443

Posted three thumbnail files from past two days. Not many miles in the first five months (mostly cold weather) and a little road miles make a big difference. From 11.8 to over 15 MPG with just 120 miles on rural highway (50 MPH average with speed varying 30 to 60) and a 60 mile trip home after fill up at 22.8 MPG. Sixty percent of my travels thus far have been less than a mile, so I'm not overly concerned with my mileage. Truck has been flawless thus far. My engine run time divided into miles traveled is under 20 miles per run hour. If I consider the testing conditions, I'm getting advertised mileage.

 

[NDRam]

Very happy with my mileage since the engine is finally settled in. View attachment 24316

Did your dash come blue like that or is that an aftermarket change? I love it!

 

[slimchance]

have you seen the image of the air flow test without a cap???

 

[slimchance]

or this one ....

 

[Barney556180]

I found this TruckTrend article on the aerodynamic comparisons between open bed (tailgate up or down), tonneau cover, and full cap.

Their tests held it didn’t matter whether tailgate was up or down.

On the main question, their testing concluded a tonneau and cap offer a similar quantifiable improvement compared to an open bed. There was better drag coefficient (Cd), lower fuel consumption (MPG), and higher top attainable speed.

Truck Aerodynamics Testing- The Snugtop Speed Showdown

The idea behind the SnugTop Speed Showdown was to see how fast a truck would go with an open bed, tonneau cover, and a cap. We used a Dodge Ram SRT10.

www.trucktrend.com

This isn’t the last word, but should be considered in the discussion.

 

[Jwsmith]

Did your dash come blue like that or is that an aftermarket change? I love it!

That's the way it came.

 

[FirstimeRAM]

The cap improves the overall aerodynamics, so less wind resistance equals higher MPG.

Maybe if you live in the plain's lands. But if you live in the northwest like i do, lugging around an extra several hundred lbs up and down hills all day is going to negatively effect your gas and brakes. Unless I NEED a cap, its not going to be on my truck.

 

[Raylan GIvens]

this is off my 1999 ford diesel cc that i drove like I stole it 20 years and ave’d 16mpg. They had no illusions about gas mileage and just left it off the sticker. I wish Ram did the same, then I wouldn't have had any expectations on mileage.

Your Ford was over the weight limit for the EPA ratings so the manufacturers don't put a rating on the window sticker. A Ram 2500 won't have anything on the sticker either. I'm sure Ram, Ford, and GM would prefer to leave it off the light duty if it were an option

 

[Willwork4truck]

Your Ford was over the weight limit for the EPA ratings so the manufacturers don't put a rating on the window sticker. A Ram 2500 won't have anything on the sticker either. I'm sure Ram, Ford, and GM would prefer to leave it off the light duty if it were an option

They might want to leave it off however I remember back in about 2010 I was hearing about new 1/2 tons getting close to 19-20 mpg. I was amazed, having owned multiple 1/2, 3/4 or 1 ton trucks since 1974 and nothing was even close to that, 6 cyl or v8. Now getting 20+ highway is commonplace on fuelly or the window stickers.
While my 19’ limited CC 4x4 3.21 likely wont see 20, at least not until past 3K, I’m pretty pleased that a heavy full sized truck gets the same mileage that 1980’s family sedans could get.
“Back in the day” 8-11 was the norm for trucks, I’m talking 60’s - 80’s. Its quite the improvement.
Now the flip side is price. You could barely spend $20-25 on a new truck in early 90’s and now? Sky is the limit.

 

[Evoking1230]

I do a lot of mixed but try to keep it on the highways, but not very successful at it lol.

I am currently getting 16.5-18. 2200 miles.

 

[Willwork4truck]

I do a lot of mixed but try to keep it on the highways, but not very successful at it lol.

I am currently getting 16.5-18. 2200 miles.

Just put on 250 miles driving up from the Raleigh area to the Appomattox Courthouse National Park, walked around then came on back. Just over a 2 hr mainly highway drive each way, NC state highways are 70 mph, most VA were 60-65. I started off at 18.2 and got it to 21.6 when I got back. I don’t even have 700 miles on the Limited so am happy with the 3.21’s and non-etorque. The transmission is silky smooth in its shifts as we went up and down the rolling hills. Good job Ram!

 

[Gman]

Yeah, that 8 speed ZF transmission is pretty awesome. It's no wonder so many car makers are using it. I love hearing the exhaust note as it downshifts approaching a stop.

 

[JohnUSA]

I'm getting over 30 half miles per gallon.