There are many ways to calculate your gas mileage. Let us all know how you go about doing so.... Here's my way:



CURRENT MPG= MILES / GALLON(S)


where,

MILES =
(OD reading at fill-up minus OD reading of last fill-up)

GALLONS = amount of gallons needed to fill up tank since last fill-up



I take a gas pump reading after the second time the pump automatically shuts off when trying to fill-up.

I always obtain a receipt with the current OD reading written on the back of it.

I use MS Excel to record and calculate averages.

 

I do esentially the same, except I reset my "trip" meter w/each fill-up and devide by # of gals to top off point. I check every tank as a matter of habit. It is a good check on other potential problems. I am not as methodical as you, as I don't use a spread sheet (do keep all receipts, though).

 

I do it the the trip OD way as well I may look into using a spreadsheet to see the averages to see how it comes out.

 

I do it with the Trip OD as well, never thought about a spreadsheet. I would think you have a way to track or record the weather conditions? Sometimes we may have 2 - 3 days with a lot of winds which on my way home is a head wind and that will reduce your mileage, same as a tail wind will help it a bit.

 

When I calculate my MPGs I fill the tank up all the way. Till I can see the gasolene touching the metal part of the filler neck. Yes, sometimes a little itty bit of gas spills out. Then I drive and fill it up the same way again. The difference in ilage calcs vs gas used is the same. The first second automatic release does not cut it for me. Maybe it's a Canadian thing?

Regards

Jean Marc Chartier