MPG Calculation, What methods do you use? , beating a dead horse I know.

[TomC]

Sort of in accurate, unless you don't run the generator-or the generator has it's own fuel tank. I know what fuel mileage I get with my bus (5-6), so when dry camping and running the generator alot, I can figure out how much fuel I burned in the generator. Like at the Escapees Tucson, I ran the generator during the day for 6 days, about 40 hours worth and burned 28 gal. Not bad considering how much they wanted for 30amp hookups.
On my truck, I have a 150gal fuel tank and a separate 75gal generator fuel tank-but with a cross over with valves if I need it. Good Luck, TomC

[lvmci]

Hi neon, in winter time, fill up as much as you can, top off. At the end of your trip, top off again, divide gallons by mileage,  voila, miles per gallon this trip. lvmci ...

[John316]

Everyone else on here is somewhat close. Actually, the best method is to calculate it based on two trips. The one should involve a lot of highway driving. The other involves city driving. Take your number of miles for each trip, and divide by number of gallons used. You should end up with something like 6.5 highway driving and 5.0 for city driving. Then take those two numbers and add them together. In this case, 11.5mpg. A guy who was looking at our bus didn't believe me when I told him we got 11.5mpg. Go figure. Some people these days

[luvrbus]

Electronic engines are easy to figure fuel mileage just plug the electronic gadget in and it tells you without any BS.
I did that to a friend of mine that had a 12 mpg (so he said) series 50 lol it came back 7.2 he told me DDR was lying   

[neoneddy]

That's one thing I was wondering about. Does a 1982 DD 6v92 have any chance at having any brains to track that?

[lostagain]

I just finished a 7 day tour with a 06 Prevost with S60 and ZF AStronic 12 speed, loaded like a rented mule with 46 pax and luggage. The dash display showed 6.5 mpg.

The newer D13 Volvo with Allison B500 in the Prevosts shows about 7 ish.

I get about 7 with my MC5 with 6V92 and Allison HT740.

The new MCI J4500 with Cummins ISX 12 liter / Allison does about the same too.

So they all get about the same.

JC

[RJ]

My Garmin GPS has both a Trip A and Trip B settings for tracking mileage.

I set it to zero when I first picked up the bus.  I have never reset Trip B, that's how I know I've covered 32K+ miles in almost three years.

Trip A is reset to zero every time I get fuel, so I know when I'm getting close to the 500 mile mark, which is my fill-up rule.

When I do fill up, I note the Trip B mileage and write it down on the receipt, then reset Trip A. 

When I park it for the day, I log into my Gas Buddy dot com account and use their "Fuel Logbook" to track my consumption.  So far, for 2017, I'm averaging 6.46 mpg overall.  I don't even attempt to break out the genset usage, other than I know it burns .5/g/hr while under load.

My MCI is underpowered with a 6V71, Allison automatic and 4.11:1 rear axle, so I'm sitting on the governor doing 60 mph at 2100 rpm.  JC has the same model as I do, but he's got a 6V92T and 3.36:1 axle, and he still gets about the same mileage.  Go figure. . .

FWIW & HTH. . .

[kyle4501]

What is your interest in MPG?
For me, it is it to know how much fuel to expect to need for a trip. Since I almost always run the generator, I include that in the fuel used - it doesn't matter what burned it - it must be replaced. . . . . .

I expect 4mpg, so far im getting around 6.5, so I'm happy 

[Jon]

I have recorded every gallon of fuel I ever put into my coaches since my first one in 1990 along with the miles, date, cost per gallon, etc.

Initially it was because I needed the documentation for purposes of tracking business expenses, but now it has become a measure of changes and how mileage is influenced. Comparing tank to tank is inaccurate. I have squeezed every last drop into the tanks as a rule and I still have had wild swings in fuel burn from tank to tank. But when I use at least 5000 mile legs or better yet, annual information I have found consistency in the MPG values.

I have had several occasions now where I had to dry camp for extended periods and where the bus mileage had almost no impact on a generator fuel burn calculation because the total mileage from pump to camping area back to the same pump was in few miles (less than 4) I have been able to get an accurate and consistent value for generator fuel burn.  The last two coaches have had DDEC so I also have been able to verify the DDEC fuel burn figures. They are extremely accurate and using them I have learned the greatest way to reduce efficiency in driving is speed or headwinds. Driving into steady 10 MPH winds out of the west for a day is the same as driving 10 MPH faster than normal speed in terms of how it affects efficiency. Ditto for tailwinds. Hills are the second greatest impact on mileage.

Towing a 3000 pound car is far better than a 6700 pound truck, but the actual difference is only about .2 MPG.

Knowing my coach and its fuel consumption is beneficial because it is how I plan fuel stops. The gauge is a nice reference, but when I pull up to the pumps I am usually within 5 gallons of guessing how much fuel I will pump in the coach. Other than that keeping the records is just a habit.

[windtrader]

Towing a dinghy consumes extra fuel. Is .5 mph about what to expect for an average vehicle? How much does weight matter? I'm trying to decide whether to get a super light vehicle or use of of the current ones.

[luvrbus]

Times have changed when I read these comments about fuel mileage all I see is the modern 4 stroke engines are pushing a 54,000 #, 45 ft long ,13 ft tall bus , tow vehicle with more HP and torque and doing it on less fuel it's amazing technology .They don't run hot either   no fighting the heating issues of the past  

[Dave5Cs]

I don't know who you are but what have you done with Clifford???

[luvrbus]

Dave, I still love my old 2 strokes I always will,now they are getting old and fading away lol I know that feeling  .Think about it for a minute RJ says 6+ mpg with a  35 ft x 8 ft wide maybe 32,000# then look at the size of later model buses running 70 mph up hill using less fuel it is amazing to me   

[lvmci]

Hi All, I have a less than 3000lb toad, a fiat. Every direction to and fro LV is mountains.  Right Now my biggest problem with my 8V92 is heat. On the long inclines like baker grade, Cajon and Mt. Pass. When I unhooked the toad and she drove it behind me up baker grade, it didn't overheat, at 10pm and over 100°, lvmci...

[RJ]

Towing a dinghy consumes extra fuel. Is .5 mph about what to expect for an average vehicle? How much does weight matter? I'm trying to decide whether to get a super light vehicle or use of of the current ones.

Don -

As you know, I flat-tow a 2003 VW Jetta Sportwagen, weighing around 3100 lbs. - which is actually less than having 35 passengers on board.

The only time I know it's back there is if I have to jump on the brakes hard because of some idiot 4-wheeler doing something stupid.  It probably does slow me down climbing hills some, but I'm going so slow anyway it's a moot point.

I see no significant difference in the fuel mileage between having the car along or going without.

Flat-towing will have less affect on fuel mileage compared to using a dolly or trailer, and yes, a 6,500 lb SUV will make a difference compared to my VW.

FWIW & HTH. . .