speedo odo help

[kris's66lwb]

if my speedo reads 5 mph faster than i am atctully going how far off shuld my odometer be and how much will thiss effect my gas milage ? the truck has 3.07s stock and the stock tire size is 235 75 15 and now im running 31 13.5s

[ToughBowtieTruck]

Originally Posted by kris's66lwb

if my speedo reads 5 mph faster than i am atctully going how far off shuld my odometer be and how much will thiss effect my gas milage ? the truck has 3.07s stock and the stock tire size is 235 75 15 and now im running 31 13.5s

Theoretically, thinking off of my head:

Not much. Think 5 miles an hour isn't much considering you have either a 15 or 20 gallon tank.Using the 20 gallon as a reference and ease of math, and also note since a 20 gallon can never be filled to 20 gallons, this is a theoretical equation to give you an idea) At 55 mph you are actually doing 50, 10 mpg at 55 (really 50) means you have 200 miles on a 20 gallon tank(50 miles per hour means you are burning 5 gallons of fuel each hour at 10mpg), so it is only a total of 20 or so miles off, or roughly 1 mpg. (20 miles divided into the 20 gallons you had=1mpg difference for each 10 miles per gallon)

In reality, just the way the stupid wind blows against my trucks changes my mpg ratings....

[kris's66lwb]

thanks josh

[Keith Seymore]

I doesn't affect your actual fuel economy at all; only the way you perceive it because of calculating it off your odo.

K