Community Forums

Crasher · 05-21-2015, 06:42 PM

Quote:

Originally Posted by dlaughlin

We're traveling from Northwest Arkansas to St. Louis. About 250 miles each way. It is supposed to be pleasant, in the mid-70s, so I'm sure the dash A/C will be more than effective. I will report back with my actual mileage though.

That might not be enough miles to get an accurate mpg due to how hard it can be to fill the tank back to it's starting point. I try to get it the same every fill, but often find the right after I get a really good mpg result, the next one is below the average. For the best and accurate information at anytime and any distance is to buy the Silverleaf VMspc software. It takes a few times to calibrate it so it's accurate, but will give you the best information anytime you want it. The ac will take some power to run it and the fan, but I have never felt a change in performance (when the fan goes into high mode) or noticed any significant mpg loss. It's there, but not noticeable.

jondrew55 · 05-21-2015, 07:50 PM

Quote:

Originally Posted by Crasher

That might not be enough miles to get an accurate mpg due to how hard it can be to fill the tank back to it's starting point. I try to get it the same every fill, but often find the right after I get a really good mpg result, the next one is below the average. For the best and accurate information at anytime and any distance is to buy the Silverleaf VMspc software. It takes a few times to calibrate it so it's accurate, but will give you the best information anytime you want it. The ac will take some power to run it and the fan, but I have never felt a change in performance (when the fan goes into high mode) or noticed any significant mpg loss. It's there, but not noticeable.

I have a silverleaf VMSpc and the only way I know to calibrate it is by filling your tank to a known level and dividing the gallons into the miles driven since the previous fill up. Then you can set a calibration factor. So it's only as accurate as that calibration.

Darwin · 05-21-2015, 08:11 PM

I notice no difference. I use dash ac. When that doesn't cool the Coach I start the generator.

Crasher · 05-21-2015, 09:07 PM

Quote:

Originally Posted by jondrew

I have a silverleaf VMSpc and the only way I know to calibrate it is by filling your tank to a known level and dividing the gallons into the miles driven since the previous fill up. Then you can set a calibration factor. So it's only as accurate as that calibration.

That's true. But, it takes several fills and hand calculations to get it accurate. I finally have mine set to less than 1/10 of a mpg difference from actual calculation over a 2000 mile distance. I had to modify the factor several times to get it that close. Now, I trust that what it's telling me is accurate.

FWIW, the OEM mpg gauge reads 35-40% higher than actual.

jondrew55 · 05-22-2015, 04:41 AM

Quote:

Originally Posted by Crasher

That's true. But, it takes several fills and hand calculations to get it accurate. I finally have mine set to less than 1/10 of a mpg difference from actual calculation over a 2000 mile distance. I had to modify the factor several times to get it that close. Now, I trust that what it's telling me is accurate.

FWIW, the OEM mpg gauge reads 35-40% higher than actual.

I know. I like getting 10.6 according to Freightliner.