I am getting 285's on my truck in the next week. i know my miles on my spedo will be off. so my question is what do i times my miles by so i can get my correct miles i drove?


thanks patrick

Your miles driven will be off by 7.5% using 285 75 16s if your truck came with 245 75 16s.

Take your Odometer miles driven, Multiply by .075 to get the extra miles driven.
Add the extra miles to the Odometer miles to get Actual miles driven.

Somebody else posted this, I found it useful.


http://www.4lo.com/4LoCalc.htm

http://dieselplace.com/forum/smileys/Big%20Smile.gifSuperlift makes a product called truspeed that will allow you to correct the speedo input for new tires. I just sold my 2002 2500HD D/A with 285's and the speedo is dead on. (I used my GPS to verify)I had it for 2 years with no problems. The truck performed better when I corrected the speed input. This unit actually changes the input to computer so it is not getting speed/rpm conflicts. Cost is between $168 and $185 online.


Can't wait to get my 2004 2500HD / LLY next week. Good Luck!