Rear axle ratio; tire size help needed

[nofortunatesonII]

I changed tire sizes on my '99 Ranger from the original 225/75/15 to 255/70/16. My truck has a 3.73 gear ratio. What gear ratio do I need to change to in order to have the equivalent to the original tire size with my new tire size? Thanks.

 

[Tbars4]

...Check out the "How to" in my signature..

 

[nofortunatesonII]

Thank-you for the reply and info...

much appreciated!

 

[IZwack]

New gear ratio = (new tire diameter) / (old tire diameter) * (old gear ratio)

Then just pick whatever gear ratio is available that is closest to the number you get (usually round up, so if you get 4.45, maybe try 4.56s since thats an available ratio)

 

[dogfriend]

My Explorer has 255/70R16 as original equipment and it was fitted with 4.10 axles.