ssbogger

How do you know how many gallons you've used? I can figure out the math part I'm not that

Plays_with_Toys

What I do is when I fill I up, I write down how many miles I have on my odometer. THe next time i fill up I write down the number of gallons I have used, then write down my odometer reading again. Subtract the first odometer read from the later one and divide by the number of gallons. So an example:

78,000 miles when I fill up
78,290 miles next fill up
Filled up with 11.6 gallons.

78,290-78000= 290
290/11.6 = 25mpg (and no, thats not what I get)

Tacoma Dude

I see you've got some tire related mods in your future.
With a wider tire you'll be getting different mileage so you can use some of your Algebra and get the speed ratio off of a tire calculator from tire rack or some other place like that and do your final MPG calculation.

I went into some detail with the math on another thread, I'll see if I can find it.

884runner

i fill my tank and set the gas. odometer to 0. when i fill up next time i know how many miles i've gone on that tank. i take that number of miles and divide it by the amount of gas i just put in.
Ex.full tank
drive 215 miles on it.
fill up tank with 14.49 gallons of gas
215/14.49= 14.84 mpg.

i hope this is how it's done if not oh well sorry.

Tacoma Dude

Okay here's the text of it:

Use the tire calculator that you'll find at different places and plug in any number to see what the ratio will be and then use the math.

For example:
Let's say you're guage shows you're got 90 miles out of the last 9 gallons. Go to the calculator and put some number like 60 mpH to get the actual mph - let's say 80.

SO to get your mpG it's going to be a ratio thing

plugged in mpH/actual mpH = your stock mileage/actual mileage

in this case...

60/80 = 90/actual mileage

if you don't remember your Algebra

60/80 x 80 = 90/mileage x 80
60 = 7200/mileage
60 x mileage = 7200/mileage x mileage = 7200

(60 x mileage) / 60 = 7200/60

mileage = 7200/60 = 120
Voila!

*EDIT*
Sorry if this came off as pedantic. I'm not sure what the math skill levels are for people here. I know older farts like myself can always say "I forgot" over "I don't know" like you young'uns

ssbogger

Thanks for all the info but all i need to know is how to see how much gas Ive used. I know how to do the calculations. I just dont know how to determine if how much gas in gallons ive used.

Say i fill up then go until i get to E. Now i go fill up again and it takes say 14.8 gallons to fill. Does this mean ive used 14.8 gallons since last fill up? I know how to calculate MPG and all that.

Plays_with_Toys

So long as you had filled up all the way the time before, then yes, you would have used that 14.8gallons.

ssbogger

Cool. So I guess thats how everyones doing it. Thanks guys!!