My New Ram 2500 6.4 MPG Update

Break-in might yield 1MPG at best...

campingken wrote:
20- 21 mpg with an HO Dodge dually?? Wow I really need a new calculator. Our 2003 non HO SRW 5.9 will hit sometimes hit 20 mpg if it's flat and the cruise control is set at 60 mph.

Man you are not going to like this then. My HO with 2WD and 3:77 rear gears hits 26 all day long at 60 MPH, the best it's ever done was 30 running behind a big truck from Perrysburg to Dayton Ohio. Note I said tucked in behind a big truck. And yes I ask him if he was good with it via the CB.

As far as the 6.4 only getting 12.5 it's not even broke in yet. My bet is it is going to top out at 16 to 17 MPG. Not bad for a big block Hemi IMO.

Don

akronharry wrote:
Posting this because people ask about the mileage:

First 300 miles: 12.2 mpg mixed driving. 2 days were in below zero weather and gas had 10% alcohol mixture.

Good info, thanks. I considered the 6.4, hoping for higher but it is what it is. Is that hand calculated or using the dash meter?

Thanks for the follow up. I suppose the cylinder deactivation on this 6.4 engine only activates at highway speeds and that maybe where the improved fuel economy over the 5.7 hemi will come into play.

AkronHarry, I didn't see if you had a Cummins or a Hemi?

20- 21 mpg with an HO Dodge dually?? Wow I really need a new calculator. Our 2003 non HO SRW 5.9 will hit sometimes hit 20 mpg if it's flat and the cruise control is set at 60 mph.

Pretty impressive isn't it? Rams with the Cummins are known for excellent mileage especially not towing anything. Mine has 3.73 axles that helps some. The 4.10's probably get a little less. I have 125,000 miles on it so as it breaks in some more it might get a little better. It got better around 35,000 miles and then again at around 80,000 miles. I don't drive a lot in town, mostly highway miles. Towing I am around 12-14 mpg and it doesn't seem to much matter if it is a 30 foot travel trailer or a 4000 pound 11 foot cabover. They are both about the same as it relates to towing mileage. The HO engine is great!

But this thread is really about the OP's Ram 6.4 gas engine so the stats should more appropriately be compared to similar gas engines like the Ford 6.2 and the GM 6.0 to be more realistic. I am sure the 6.4 will do well in that arena. The OP also is plannng to tow a 29-30 foot fifth wheel next summer so that will provide realistic fuel mileage numbers for the 6.4 towing around 10,000 pounds or more.

20- 21 mpg with an HO Dodge dually?? Wow I really need a new calculator. Our 2003 non HO SRW 5.9 will hit sometimes hit 20 mpg if it's flat and the cruise control is set at 60 mph.

No truck is going to get good mileage in mixed driving and below zero temps. Wait until summer to get a good idea.

I am assuming it will get better. Had a 2005 Ford 250 diesel and never got 20 mpg not towing. Since it is not a DD, I would be perfectly happy getting mileage in the mid teens. We will see.

Hopefully it will get upwards of 16-17 mpg when broken in. 300 miles is not many miles to get a good handle on mileage.

start an account over at fuelly and put a link in your signature noting your vehicle. Then people who are curious will be able to check your profile and compare mileages. Boy, 12.2 is a bit lower than what I was expecting to be honest, I was hoping to see 14 or 15 mpg mixed. But the thing is practically brand new. Get a good couple thousand miles on there and hopefully we'll see improvement.