MPG on 6.9 Cummins

[retiredtraveler]

My bride and I just finished our second 2-week trip in our new to us 1998 Holiday Rambler DP. As anyone who has ever travelled New England knows nothing is straight or flat here. Up and down (Seems mostly up) around and around to grandmas house etc,,,,,,
The best I can tell we have the weenie 275 HP engine. Coupled with the 6 speed Allison it did good. We did not win any speed contests but even the steepest hills kept us around 40-45. With a Malibu in
tow that brought us up around 28,000 lbs total.
Over that 1000+ miles I have calculated the mileage thus far to be 10.4 MPG.I know many factors play in and will monitor mileage (I'm a math geek)
I'm happy for now anyway.

[vegasfoodguy]

I too have an ISB 275, Presently in Idaho,Just figured my MPG, Boise to Coeur d Alene, Some very steep hills, lots of exhaust brake and keypad shifting for the Allison, 10.1 towing Jeep Grand Cherokee.

Not speedy up hills, but very strong and cool.

Terry.

[tkranz]

I get almost exactly the same with my ISB 275hp in a 98 Winnie Vectra. Average 10.3 over many miles. Occasionally in the 9's and sometimes as high as 11.

[Passin_Thru]

Good driver. Now go out west in the wind and mountains and shock yourself. I got 10.8 Westbound from VA-NM-CO and CO-VA got 9.7. I really try to get my best but can't always do it because some fool in a 777 keeps catching up with me.

[J_Walker]

10.4 MPG for the combined weight of 28,000 lbs is good. The way you drive is a big factor. I had a Cummins 5.9 ISB and got 10-11 MPG towing a Malibu. I never considered the ISB to be small, I considered it to be just right. My new MH has a 6.7 ISB.

[ScottG]

That's pretty impressive!
(BTW it's either a 5.9 or 8.3L)