what is the formula for new gears when you get bigger tire size?

 

What gears do you have and what size tires are you getting?

 

 

I like this chart a little better, applies to our trucks better

 

i dont want the chart i want the formula i know how to use it i just for get it can i plz have the formula

 

Its the same chart. LOL A couple of the numbers are 1 number off but it is the same thing.

 

Oh well its easier to see for me, colors stand out more

 

Just cross multiply then

Stock tire size 29 = 4.10s
New tire size 35 = x

35x4.10=143.5
143.5 divided by 29 = 4.94

So the right size would either be 4.88s or 5.13s

 

thank you i jsut want to run so number and try and figure some things out

 

that chart is bull**** my tack at 65 is about 1700 with 3.27s and 31s

 

You don't have stock tires. Which means your tac is off. Its not BS.

 

Charts dead on for me, are you sure you have 3.27s?

 

that means nothing i have a new speedo gear to make it right all my stuff is correct

and yes sadly i have 3.27s gears

 

You need to have it calibrated. If you haven't then your speedo gear is nothing. And that chart is dead on for me and my 33's and 4.10's.

 

What does he need to have calibrated? When he changed the speedo gear it fixed everything.

 

I thought you have to take and X-cal or something to it.

Either way, the chart is not bull****. It is dead on.

 

my speedo is cable driven not electrical so and im and OBI truck so i couldnt use an x-Cal any way

that chart is wrong when i had 3.27 and 235 tires which is 28.9

 

Naw, his speedo isn't computer controlled.

 

Oh yeah forgot about being pre 98. Anyway I don't know anyone that has had a problem with this chart.

 

that chart is based off of 65 mph right?

 

Yes

 

But what gear were you in? Are you an auto or manual? Those play a part in this too.

 

holy crap guys! think before you speak! the chart does not know your overdrive ratio in your trans, it is a generic chart probably using 1:1. you can not figure out the speed or gear ratio the chart is based on without knowing one of those two numbers

 

I never said if it was right or wrong, I just said it was right for me

 

im talkin about 5th gear with 3.27 gears and 31s someone explain this chart to me i might understand then