Hi Guys,

My new lift kit is 6" procomp with 20X10 wheels & 35X12.50R20 tire size .
I don't know if i should to change may gear ratio (ring & pinion set) ?
If i should to change it .. what is the best choice for me & what to do for the front axel ?

P.S. My axel code is 19 (3.55) And the stock tire size is P255/65R17 .

Please anybody can help me with this ?


MY TRUCK --> F150 XLT 5.4L 4X4 (2004)

 

if you take the percentage of increase in the overall diameter of your tire swap, you will have the percentage needed to change your gear ratio to get back to near normal acceleration rate. don,t forget to fix speedo.

 

Thank you s1037s ,

Yaa sure , Regarding the speedo My Edge Evo. On the way ..
But still donna know what gear ratio I shoult to chose !!

 

4.56 would be the closest to get you back to the right RPM, also you will need to do front and rear, Presision gear makes the highest qaulity i have seen. good luck

 

4wheelparts.com has a good gearing chart, But a 4.56 sound about right. your speedo may be corrected by the gear change. I put a 4.10 with a detroit tru track posi with 33" 2wd. tire size was 255/70/16 and it brought it back a little lower than stock 3.55. I am happy with it.

 

4.10's get u closest to stock rpms(wouldnt have to recal) but 4.56 would be a better choice do to the added weight of tires/rims


go 4.56 you love the extra power

 

i second the 4.56 gears