I was driving on a country road today with the cruise set at 50mph. I was in 4 cylinder mode for about 20 minutes and checked out my gas mileage. To my suprise I was seeing 27mpg. 2009 hemi ram sport 3.55gears.

I snapped a picture with my phone for proof. Level road, no elevation changes. Cut corn fields on each side of me. No drafting.

 

Those looooong downhill runs are sweet!!!!

 

No hills in Iowa. It's as flat as can be where I was driving.

https://dodgeforum.com/forum/4th-gen...xperiment.html

It's not the 1st time that I've done this study. I drive the same road everyday and get similar results.

Take a look at the mileage. If you know of a 5 mile slope in Iowa, send me a picture

 

I can't get mine that high going downhill

 

My other tests have been with 3/4 and 1/2 tank tests. This time I was a little over a 1/4 tank and was able to set my cruise at 50mph without MDS shutting off.

In conclusion our trucks get 25mpg when MDS kicks in when your going 45-50mph.

This was actually test #4 back in October from my 1st study.

 

I think that would be at a slight decline but I take what you have said at face value. The fact that you are doing like 80kph really makes the difference. Are you a farmer? those are the only ones I know that go that slow on the highway.

 

All I see are 440acre (1sq mile) farms on both sides of the road for 20 miles on this road. I'm not on a highway. I drive on a 2 lane road that's a county B connector road, which means it's 55mph with no posted speed limit. I just drive around 48-50mph to stay in 4 cylinder mode. Anything over 50mph the V8 mode kicks in and the truck gives me around 15-16mpg.

 

I didn't mean any offence. Where I am is the same way, but a slight grade none the less. don't discount downhill travel to the cause of your miracle mileage

 

Hand calculate the MPGs and see what it actually is.

 

I believe it.

I went out for a 100mile drive one way yesterday and reset the average mpg.

Regular cab, short box with 3.92 gears at 65 to 75mph with the cruise.

Slightly hilly, and saw 20.8mph at destination, and 20.2mph on the way home.

Just picked her up last week, so the truck only has 200miles on the clock.

Taller gears, lighter foot, broken in engine with a bit of a tail wind and I wouldn't discount the OP's experience.