Bad fuel mileage 5.7 hemi

[RAM Patriot]

So they lower the test results 10% and still it's just about impossible to match what the Window Sticker says.

That's what they say.

I would like to see the calculator that they use and the course that they run.

Must be downhill both ways.

 

[TangoFoxtrot]

Totally agree. It is nice when you want to kind of enjoy letting the truck do its thing...but not as fuel efficient as letting off the gas to slow down.

I had active cruise on my tacoma, it was great for those long backroad routes where you cannot pass and are stuck behind someone for miles on end. But it is horrible for any highway driving in the city. I always got the worst mileage using active cruise, 2nd place was regular cruise and first was always not using cruise. I've found I can squeeze about 1-1.5mpg better not using cruise on the Ram, but for long trips I get lazy and just set the cruise.
Fuel mileage is so subjective and really depends so much on your environment, how you drive and how long you have to sit at lights. I'll be hovering around 18.4 (computer), then go drop my kids off at school and will be down to 16.5ish by the time I get home through all the traffic lights. But if I just stick to my regular work commute (highway) I can keep in the 18s, until the winds pickup and drop it down. Simple things like remote start will immediately drop my avg by .2 ever time.

 

[KY2021Laramie]

I have a 2021 Laramie 4x4
3.92 gears 5.7
E torque 4500 miles on the odometer
averaging 19.6mpg

 

[Patamaran]

Seems like every complaint about fuel economy, comes from a member that has 3.92 gears in their signature. My brand new 5.7 hemi 3.21 is getting about 18-19 MPG. it only has about 200 miles on it. Apparently it goes up after break in, i'm very satisfied.

 

[Biesty]

Apparently it goes up after break in.

I always question this statement. When the truck is new you don't have average mileage built up. So every time you idle at a stop light or if you have a lot of start/stops it will kill your mileage. Once you have a few thousand miles on the truck your average is less effected by the idle or stop/start which could look like you are suddenly getting better mileage. I only have 1,000 miles myself so maybe I haven't got the chance to notice the improvement (I sure hope that is the case)??? But I'd like anyone that believes they have increased gas mileage after break-in to either reset their average and start fresh again or look at immediate mileage. I can say I don't notice any better immediate mileage yet but my average is starting to do much better than the first 100 miles.

 

[Patamaran]

I always question this statement. When the truck is new you don't have average mileage built up. So every time you idle at a stop light or if you have a lot of start/stops it will kill your mileage. Once you have a few thousand miles on the truck your average is less effected by the idle or stop/start which could look like you are suddenly getting better mileage. I only have 1,000 miles myself so maybe I haven't got the chance to notice the improvement (I sure hope that is the case)??? But I'd like anyone that believes they have increased gas mileage after break-in to either reset their average and start fresh again or look at immediate mileage. I can say I don't notice any better immediate mileage yet but my average is starting to do much better than the first 100 miles.

easy way to figure that out, hand calculations over a set trip during break in, and compare the same trip after a few thousand miles. not all variables are perfect, wind...etc but it could give you a pretty good idea weather the truck improved or not. i know my V6 ram improved by 1-2 mpg after break in using hand calculations not the display.

 

[41magmag41]

with the computer, 3.92 rear end regular 8 speed, my average is 18.5 to 19.8. combo driving in town and highway

 

[Carlos.33193]

I'm down to 9-10 MPG city and around 15 highway.

37" tires (6 inch lift), 3.92 gears, auto start stop disabled.

 

[RAM Patriot]

Found a calculator that will allow you to compare the annual cost of fuel for two different cars or two different fuels.

Here what I found for my truck using E-10 / 89 octane fuel vs running Non-Ethanol fuel 90 octane.

The truck averaged 17 MPG on the ethanol fuel due to the lower BTU's ( ethanol has 30 percent less energy than gasoline).
I averaged 20 MPG on the non-ethanol fuel driving the same route to work every day.

Actually saved a little money over the long term even though I paid more at the pump. I was able to drive more miles on the non-ethanol fuel.

I also noticed that the truck seemed to go into ECO mode easier which I believe led to better MPG.



Here is the link to the calculator: http://calcnexus.com/fuel-cost-calc...ce1=2.674&price2=3.169&mpg1=17&mpg2=20&calc=1

 

[HeavyRotation]

Found a calculator that will allow you to compare the annual cost of fuel for two different cars or two different fuels.

Here what I found for my truck using E-10 / 89 octane fuel vs running Non-Ethanol fuel 90 octane.

The truck averaged 17 MPG on the ethanol fuel due to the lower BTU's ( ethanol has 30 percent less energy than gasoline).
I averaged 20 MPG on the non-ethanol fuel driving the same route to work every day.

Actually saved a little money over the long term even though I paid more at the pump. I was able to drive more miles on the non-ethanol fuel.

I also noticed that the truck seemed to go into ECO mode easier which I believe led to better MPG.

View attachment 90600

Here is the link to the calculator: http://calcnexus.com/fuel-cost-calc...ce1=2.674&price2=3.169&mpg1=17&mpg2=20&calc=1

Wow your gas prices are super cheap. What state are you in?

 

[RAM Patriot]

Wow your gas prices are super cheap. What state are you in?

Georgia.

We are one of the states that the pipeline goes through.

 

[Biesty]

Found a calculator that will allow you to compare the annual cost of fuel for two different cars or two different fuels.

Here what I found for my truck using E-10 / 89 octane fuel vs running Non-Ethanol fuel 90 octane.

The truck averaged 17 MPG on the ethanol fuel due to the lower BTU's ( ethanol has 30 percent less energy than gasoline).
I averaged 20 MPG on the non-ethanol fuel driving the same route to work every day.

Actually saved a little money over the long term even though I paid more at the pump. I was able to drive more miles on the non-ethanol fuel.

I also noticed that the truck seemed to go into ECO mode easier which I believe led to better MPG.

View attachment 90600

Here is the link to the calculator: http://calcnexus.com/fuel-cost-calc...ce1=2.674&price2=3.169&mpg1=17&mpg2=20&calc=1

Uhm, aren't you interpreting your results backwards. It appears it is $17.34 less annually on the E10/89 gasoline. If my calculations are correct, any mileage over 5 miles per year you will pay more for the non-ethanol. But that is a handy calculator.

 

[RAM Patriot]

Uhm, aren't you interpreting your results backwards. It appears it is $17.34 less annually on the E10/89 gasoline. If my calculations are correct, any mileage over 5 miles per year you will pay more for the non-ethanol. But that is a handy calculator.

Your right, you only save $17.34 using the ethanol.

Pretty much a wash, at least for me.

 

[Biesty]

Your right, you only save $17.34 using the ethanol.

Pretty much a wash, at least for me.

Completely agree. For $17 annual savings I'd use the non-ethanol for the savings to the entire rest of the fuel system. In reality it maybe would save you in the long run by not having the ethanol running through it.

 

[392DCGC]

Seems like every complaint about fuel economy, comes from a member that has 3.92 gears in their signature. My brand new 5.7 hemi 3.21 is getting about 18-19 MPG. it only has about 200 miles on it. Apparently it goes up after break in, i'm very satisfied.

Don't trust the computer readout. It's frequently 1-2 MPG optimistic. Hand calculations are your best bet. And no, MPG doesn't really go up. My 3.21 5.7 eTorque has a fairly flat line in regards to its lifetime MPG of 17.7 (nearly 10,000 miles). I drive pretty conservatively too.

I always question this statement. When the truck is new you don't have average mileage built up. So every time you idle at a stop light or if you have a lot of start/stops it will kill your mileage. Once you have a few thousand miles on the truck your average is less effected by the idle or stop/start which could look like you are suddenly getting better mileage. I only have 1,000 miles myself so maybe I haven't got the chance to notice the improvement (I sure hope that is the case)??? But I'd like anyone that believes they have increased gas mileage after break-in to either reset their average and start fresh again or look at immediate mileage. I can say I don't notice any better immediate mileage yet but my average is starting to do much better than the first 100 miles.

The computer only keeps a rolling average of about 500 miles. No screen on the truck will track MPG beyond that. Even if you have 10K miles on your trip computer, the MPG readout is not over that 10K miles. Why RAM couldn't bother to engineer a long term MPG tracker is beyond me. But, as mentioned, it's fairly worthless anyway because the accuracy is poor.

Found a calculator that will allow you to compare the annual cost of fuel for two different cars or two different fuels.

Here what I found for my truck using E-10 / 89 octane fuel vs running Non-Ethanol fuel 90 octane.

The truck averaged 17 MPG on the ethanol fuel due to the lower BTU's ( ethanol has 30 percent less energy than gasoline).
I averaged 20 MPG on the non-ethanol fuel driving the same route to work every day.

Actually saved a little money over the long term even though I paid more at the pump. I was able to drive more miles on the non-ethanol fuel.

I also noticed that the truck seemed to go into ECO mode easier which I believe led to better MPG.

View attachment 90600

Here is the link to the calculator: http://calcnexus.com/fuel-cost-calc...ce1=2.674&price2=3.169&mpg1=17&mpg2=20&calc=1

Math on that just doesn't work out. Namely, fuel with 15% ethanol content will only have 5% lower BTU overall. So how exactly do you get 18% better fuel economy by skipping the ethanol? I don't buy it.

 

[IvoryHemi]

I’ve been surprised how accurate the avg mpg readout has been per tank. So far it’s always within 0.5 mpg of actual

 

[RAM Patriot]

Don't trust the computer readout. It's frequently 1-2 MPG optimistic. Hand calculations are your best bet. And no, MPG doesn't really go up. My 3.21 5.7 eTorque has a fairly flat line in regards to its lifetime MPG of 17.7 (nearly 10,000 miles). I drive pretty conservatively too.


The computer only keeps a rolling average of about 500 miles. No screen on the truck will track MPG beyond that. Even if you have 10K miles on your trip computer, the MPG readout is not over that 10K miles. Why RAM couldn't bother to engineer a long term MPG tracker is beyond me. But, as mentioned, it's fairly worthless anyway because the accuracy is poor.


Math on that just doesn't work out. Namely, fuel with 15% ethanol content will only have 5% lower BTU overall. So how exactly do you get 18% better fuel economy by skipping the ethanol? I don't buy it.

There are a couple of other factors besides the BTU rating that could be affecting the difference in MPG between the ethanol and non-ethanol.

1. The non-ethanol fuel that is available in my area has a higher octane rating (89 vs 90). So the engine is running more efficiently from the higher octane rating. (10.5:1 Compression ratio)
2. Ethanol is hygroscopic, which means it absorbs water, and we have had a wet spring / winter this year. If the ethanol fuel absorbs too much water, phase separation occurs - the ethanol comes out of solution with the gasoline. Essentially, the mixture breaks apart. When this happens, it destroys the quality of that gasoline and strips away a good amount of the octane rating of that fuel. You end up with poor quality gasoline.
3. The amount of ethanol can vary from tank to tank or from pump to pump. Even though I go to the same gas station. The ethanol is blended with gasoline at the fuel terminal to make E10, E15.
4. Our engines were not engineered to run flex fuels so I believe they run more efficient on 100% gasoline.

Try it for yourself, don't trust me.

If you do decided to try it, I did discover it took about three tanks of non-ethanol fuel for the engine to get the best mileage from the non-ethanol fuel. Perhaps it took that long for all of the ethanol to work out of the tank or for the ECU to respond to the higher BTU fuel.

 

[bobf5761]

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?

mine is a 2019 ram rebel, only getting 7.5mpg, bout ready to shoot it

 

[silver billet]

Well if you're getting that bad MPG you can't be driving it very far nor filling up that often, so don't worry.

 

[SD Rebel]

Well if you're getting that bad MPG you can't be driving it very far nor filling up that often, so don't worry.

Matches me to a tee. I work from home, lots of my driving is around town, which is evident at my 11-13 mpg range average. But I may only fill-up once a month.