Forum Discussion

americanrascal's avatar
May 12, 2015

Mileage surprise

Our Itasca Sunstar 31KE (gas F53 chassis V10)is less than a year old and running fine. We tow a dolly with about a 3k lbs car on it. Last week I decided to really hone in on the mileage issues while on a one thousand mile trip south to FL and then back north to home. Over the course of the week long trip I went through four fuel stops.

Road conditions were good all the way and the geography began in the piedmont of GA and ran down through the coastal plain of GA into central FL. About 1/2 the trip was interstate the rest was 4 lane limited access. Speeds started for the first 2 hours at 55 then were consistently 62- 63 thereafter. To limit downshifts I don't use cruise control on hills.

My first tank I got right at 7.1 mpg running a varied 55 to 63 mph in the piedmont down through the coastal plain then onto I-75 south.The second and third tanks ran about 6.2 and 5.9 mpg mostly through Florida (flat and four lane- about 30% city driving). My speed on the hiway was set at 62-63 MPH

The last part trip was no city driving-some uphill into and across the piedmont headed north, all 4 lane 65 MPH posted highway, limited access back across gently rolling hills of GA. As I didn't have any time constraints I opted to poke along at 56- 58 all the way home to see what would happen to the mileage for the last 250 miles- averaging about 5 mph slower than the first part of the trip.

When I got home I checked the mileage- and was pleasantly surprised to find my mileage had jumped to 8.9 mpg (from 5.9)!I knew it might be better but not that much.

I am now contemplating holding at 56-57 on highways from here on out That's not a bad increase for an 80 gallon tank. Will continue to check.Sure I may have an extra hour of driving time on a long days run on the road but I can probably get used to it.

Anyone had a similar experience on that general type of gas rig?
  • Effy's avatar
    Effy
    Explorer II
    I don't track my mileage any more. I used to sweat over it, but it would never dissuade me from making the same trips so I figured why bother. I have no idea what I am getting and it's blissfully liberating.
  • I do see your point about driving slower will increase your mpg; however, I have to agree with others. The 8.9 sounds really good, but in reality it means nothing as too many factors will come to play. Only measuring the "average" mpg over a long period of time, lots of miles, and different driving conditions can one truly know his mpg.

    I have a small excel work sheet that I use to keep track of miles, gallons, price, and mpg at each fill up. With my previous dp, over a period of about six years, I averaged about 8.6 over 36,000 miles...with single measurements varying from 5 to 12 mpg. Our new dp, with only 4000 miles on it I'm only averaging 7.4 mpg.

    Continue to keep track and only be concerned with the average mpg.

    Happy travels..

    Ron