how do our trucks tell the speed we're going?
how do our trucks tell the distance we have traveled?
...my thoughts and my confusion
when you move up in tire size, the speedo will read lower than actual speed due to the diameter of the tire being larger than stock causing you to travel a longer distance in the same amount of rotation. so in my case when i went from the stock to a 285/70/17, my speedo would read 60mph while i actually was going ~64mph. that all makes sense..
tire calculator to figure change in speed from the change in tire size
the confusion sets in when you re-gear...
so now i have 4.56 gears with my 285s...
using the formula set forth by WhatThePho? in http://www.tacomaworld.com/forum/per...r-formula.html, my true speed is now .846 of my speedo reading...
so now when my speedo reads 65mph i'm really going 55mph
does this also mean that the mileage on my odometer will read higher than the actual mileage traveled? if it reads 100 miles, does it mean i really only went 84.6 miles?
and this is where the question came up...how exactly do our trucks calculate the speedo and odometer readings?