Left the RV in Alberta at the BILs and came home empty.

To first fill:
221 Km (136.41 miles) used 23.5 L (6.21 US gal) diesel fuel = 21.96 US mpg

For the metricans:
221 Km/23.5L = 10.59L/100Km

Second fill:
469 Km (289.5 miles) used 50.2 L (13.28 US gal) diesel fuel = 21.79 US mpg


Conditions/settings:
- 2007 (5.9L Cummins) Dodge Megacab 4x4, 3.73 gears, auto trans
- Relatively flat terrain
- Temp mid 80s, not much wind that day
- Ran A/C the whole way
- Cruise set at 106 km/h (65 mph)
- Cargo bed full of junk/camping gear/bikes
- No topper/tonneau cover
- Stock sized tires
- No lift
- OE Tires at 80 psi rear, 60 psi front
- Hypertech on stage 2, truck all stock otherwise


Towing mpg was as high as 11.6 mpg, and as low as 10.0 mpg. The 11.6 was no A/C and no wind, and the 10.0 was over mountainous terrain with a 90 Km/h (55 mph speed limit). RV is a 36' 5th wheel weighing in at about 11,500# - GCW was about 20,500#.

I'm pretty happy with the numbers and had to brag!

 

Thanks for the details of the conditions in which you calculated the mpg's. Is this hand calcualted? Thanks. pcm

 

Nice numbers!

 

The O/H only goes to the tenths spot, no hundredths, so it would have to be hand-calc.

 

Thanks pcm

 

Don't worry about it, we all have our issues. I like to wear socks when I'm barefoot.

 

That is just about what I got a month ago on a trip from SF Bay Area to Missoula, MT and back. Best tank for the trip was 22.3 MPG, and worst was 20.9 (hand calculated of course). Nice to only have to fill once going each direction.

 

Numbers are all hand calculated. Distance driven divided by fuel used.

I should point out that this is about the best mpg I have got with this truck. It will do 20 easily (which is the norm) but almost 22 was something I had to brag about.

 

I wanted to make sure your math was on target...

221km = 137.3 miles
23.5l = 6.208 gallons

22.11MPG

469km = 291.4 miles
50.2l = 13.26 gallons

21.97MPG

 

I used miles = Km / 1.6
And 1 US gal = 3.78 L

Close in any case.

 

Do you have the fuel tank vent kit??

 

Congrats ib516, my truck used to do that well until I had to have bigger tires.

 

Ya but my way got you 22+mpg.

We all know when bragging to friends you must use the most extreme scenario possible without actually exaggerating.