5.4 MPG

[SharpPI]

We took our maiden voyage this past week in our new 2017 Forester 3011 DS. Next week I have to take it back to the dealer ... I have a list of little things that need fixed and I will do another thread about that later.

We pulled our 2014 Ford Escape on our Roadmaster dolly from Eastover, SC to Edisto Island, SC. Because we had teenagers riding in the back I let the generator run while on the road so I could keep the coach AC running. While camping we lost power, because of a big storm, and had to run the generator for a little over two hours.

On the way home we stopped for fuel, adding 30 gallons and I computed the mileage, like all good men do , and found that we averaged 5.4 mpg. I was shocked it was so low ... I was expecting about 8.5 mpg.

Is this normal?

[Big Red and 30WR]

OUCH

[grumpy0374]

Your running a fully loaded out 30 ft class c, towing a vehicle, on a dolly, while running your genny. That's probably in the "good mpg" for what your hauling. Yes, I would say that's "normal".
8.5 mpg is probably attainable, with just your rig alone. But your loaded and towing and running your genny. Don't know who told you to expect 8.5 mpg with that load.
Just accept it, move on, and enjoy the rig and trip with family. If you are going to constantly worry about mileage , and spending a few bucks , your not going to enjoy the experience.
Grumpy

[funfinder5]

Don't go by one tank/fill up. We're you full when you left, did you fill it or the dealer?

How fast were you going?
We tow a Prius on a dolly and are loaded to (let's just leave it at that) GVWR on our 3170DS. We have three pre-teen/teens and all most always have the generator running. I try to keep the speed at or below 65mph and we average in the 7-8mpg range.

Give yourself a half dozen trips to get use to driving it and I have to keep telling my right foot we have 17,000(+-)lbs behind it as it's easy to forget sometimes.

[RamblerGuy]

I agree with funfinder. The gas tank has a flat top and if the coach is low on the driver's side you will not get it completely full. At the next fillup you'll think you used more gas than you actually did. Don't make a conclusion until you've made a few trips.

Also, did you deduct the two hours of gas consumption in the campground when you did the math?

For reference, running the generator will drop your apparent mileage about 0.5 mpg if you were otherwise getting 8 mpg at 60 mph.

[Steve29rlx]

Hey, that's better mileage than folks are getting dry camping running a generator. Some times they go through periods where they get zero mpg, if they are running their generator but not driving.
If you want to find out what your mpg is you will need to fill up on the road twice. Camping time spent running the generator really can't be figured in the mix.

[RubberNail]

Running the A/C on generator takes about 0.6 gph. My experience after a couple of days dry camping and fits in with what I've read. Multiply the hours of generator time by 0.6 and deduct that from your gas use before computing mpg. Running against ANY headwind will also take down the numbers. Towing my Malibu cuts about 0.5 mpg. And as others have said, fill ups can vary 4 to 5 gallons depending on pavement slope.