Golden_HVAC wrote:
I used to fill my work truck up at Shell stations all the time, and got 10 MPG, so I figured that the 30 gallon fill was good for 300 miles and 33 gallons for 330. Once I was not near a Shell, and used Cheveron. I was getting 11 MPG on Cheveron gas, and Mobil. Shell and Arco only gave me 10 MPG. This was a E-250 van.
You might keep a log and start buying only Cheveron and Mobil.
As a side note, I bought 91 octane gas for my trip from San Diego to Oregon in 2013. I was getting 8.5 MPG while running 55 MPH. Normally I was only getting 7 mpg, while running 65 MPH. So the improved octane and slower speed really paid off in lower fuel costs! For a 1,100 mile drive, that is more than a few gallons. The extra 5% in fuel cost per gallon saved me about 10% in fuel used. Slowing down helped fuel use too.
I think that you will get about the same MPG with the slightly longer class C as the older one. It will be slightly heavier, but also have the new 5 speed automatic transmission, so it should get better mileage if all things (weight and height wise) where equal. Of course slowing to 55 MPH will push a lot less wind out of the way, improving mileage substantially!
Changing to 91 octane will help the MPG of any fuel injected vehicle. Try it and see! The anti-knock sensor will see that the fuel is better, and can run the car leaner, and advance the spark for better HP per gallon of fuel.
As for running Chevron fuel , I can agree ,my Harley FB pinged on all other Brands of fuel except Chevron.
Running 91 octane in a vehicle that is designed to run 87 octane is wasting a person's money.
My guess by your comment of Chevron/Mobil getting better MPG You filled up with Chevron for your trip up to Oregon .
You driving slower is what got you the better MPG Not bumping the octane.
But if it makes you feel better running a higher octane fuel, its your money. ;)
Just google running higher Octane effects !
Here is a good read on Octane... Of many...
http://blog.hemmings.com/index.php/2014/04/11/tech-101-octane-the-facts-and-the-fiction-behind-those-higher-priced-fuels/
