new gear ratio

[kil roy]

ok i did a search all be it in vain for what my new

gear ratio is with the larger tires.

i know it made a difference by how the truck feels

while taking off now.

would appreciate if someone knows for sure.



went from 255/70/16s to the 265/75/16s with a 4.10

im guessing around 3.94 final but would like to know

for sure.



thanks in advance

Rich

 

[Todd Z]

I got 3.88:1.... Just some quick math, IT may be wrong...



Todd Z

 

[Dan Long]

Try this

 

[kil roy]

Dan,

thanks for the calculator its what i was looking for and has been saved to

my favorites.

Todd you and i were both close i was high by 3 and you were low by 3

calculator says it is now 3.91.

 

[Dan Long]

No problem.

 

[Richard Weihert]

Excuse my lack uf understanding but how does the tire size alter the gear ratio?

 

[Dreman]

The tire size does not affect the gear ratio. Instead it affects the "effective" gear ratio. What he's saying is that the larger tire makes his truck drive like it has a 3.91 gear ratio rather than the 4.10 ratio his truck is equipped with. It's just a quick and dirty way of getting a handle on how a tire size change will affect the performance of the truck.

 

[Richard Weihert]

okay good I am not crazy. Is there a noticable difference. from a 4.10 to a 3.91. I would think it would be a little slugish maybe a 150-200 rpm change. more of the concern would be the spedo error.