Question Fuel Mileage Check

[Just George]

I have a mpg question for those with new / newer diesel pusher coaches. I had a 2015 Ventana that I bought with about 14K miles on it and fuel mileage per the onboard computer ran pretty close to 8.0 mpg for the 5 years I owned it. Enter our 22 Dutch Star. First trip of approximately 2000 miles, we ran 5.0 mpg. Just wondering if the 5.0 mpg is typical or perhaps there is something amiss with the new ride.

 

[MapNerd]

Seems low for flat land but if you are doing a lot of climbing or driving in high temps with generator running and ACs blasting, or driving in low temps with the furnace running, that seems right. Also, any changes between what you pull? Perhaps now you pull a double stacker with all your toys and before you just pulled a car, for example Any driving pattern changes?

 

[Just George]

@MapNerd Thanks for the reply, No generator or furnace running, limited AC use pulling the same toad. A portion of our trip did have some mountain climbs so less mpg is expected there but most was flat land. I did notice this coach runs ~ 1650 RPM at 65 mph, our 2015 ran ~ 1800. This seems a bit strange to me since the Dutch Star is heavier than the Ventana and about a foot higher I would have thought if there was a drive gear ratio difference i.e. higher gearing, then I would see somewhat higher RPM. Of course there's not much RPM head room there since I think the max RPM is 2100. This is acting like there is a lower gear ratio. Just trying to figure out if this is typical performance or if it's something to add to the Freightliner warranty item list.

 

[MapNerd]

Based on what you describe, I would ask them about it. 5mpg seems low. I am in a 2020 Ventana I can usually get 7 or 8

 

[Buly]

My DS averages 7-8 mpg fully loaded and towing Honda CRV. Never seen 5 mpg.

 

[Bob K4TAX]

Different shape vehicles, different wind resistance. Plus noted headwind, tailwind, crosswind. ???????? Just sayin' ..... could be. Our truck, pulling our trailer, will vary +/- 1 or 2 MPG over the same trip to and from. What's different? Load, wind, and etc.

 

[J&JD]

Our 17DS also runs close to 1650@65mph give or take a few revs. 45k miles on the unit with much of the driving in the mountain filled west. 7-7.2 is what I average constantly, always towing a 2012 Wrangler.
I would be concerned with a 5mpg average but I would certainly give it a longer trial period before getting too excited. Course at the price of fuel these days……..

 

[Neemer]

Are you relying on your coach to tell you the mpg or are you manually calculating?

 

[Buly]

I have done it both ways, and they were very close, between 7-8 mpg.

 

[Just George]

Thanks for your input folks, Seems like our Dutch Star is running somewhat low mpg. Hopefully this is not a feature of the 2021 Cummins. Coach has ~ 3500 miles at the moment so still in break in but appears to be worth a mention at my next Freightliner Service.

@Neemer Yes relying on the coach computer for mpg, both the 2015 Ventana & the 22 Dutch Star

@Bob K4TAX Variables understood. 2015 Ventana experiences all of those various wind conditions and managed to average at least 8.0 mpg. Dutch Star has also experienced various wind conditions & never seen more than 5.0 mpg.