Just need a quck answer. I have put new tires on my truck and went from the stock 2wd 245's to 265/70 Bfg's. My question is what new rearend gear is need to to put my speedo back to stock. Right now i am about 5 mph too slow. I am thinking about putting some 4.10's to replace the 3.08 i have now. Will this put me near stock or am i still gonna have to recal the speedo?

thanks
Ed

 

4.10 gears will not bring to stock it still abit off 4.10 is almost correct for 35in tires or 315's best off to take the truck to the dealer or use a cheap programer to recalibrate it sence your not far off, the computer will alow for tire change up to 35in tire but to do this you must know how many times the tire rotates per mile exaple a 35 rotate around 599 times a mile. if you still choose to add new ring and pinion gears there is a formula out there somewhere some one well know how to calulate it
but your tires are not much bigger than stock i wouldnt change my gears if i was you unless you plan on doing some major towing.

i plan on going 4.10's with 35's with is almost the stock 1to 2mph off. on your 265's that way to low, mpg on highway would be terriable