one54ton

My speedo is off and id like to know how fast im going. At what RPM am I at when im goin 65? I have 35s and 4.10s.

jman

try this page, might help you out
jman

http://www.klenger.net/dodge/general...calculator.xls

BIGROD

If your truck had 265-75R/16 from the factory, the speedo is off about 2 for every 10. I went from 29's to 33's on my Dakota and thats what it is off. So that would means that speedo reading 55 you would be running 66.

It is not a perfect scale but will keep you from getting a ticket. I drove using this scale for 4 yrs. and never got stopped for speeding.

Hope this helps,
Rodney

one54ton

Great..the calculator wont download thanks to my P.O.S. computer...anyone else?

need12v

get a superlift truspeed calibrator and enjoy the correct speed reading. Do a google or yahoo search for speed calculator, and you should find several places online to calculate the corrected speed. I have 285's (33's) and 4.10's and when I am going 66, it's really 70.

fschiola

Here's 2 calculator's you can use.

Here

And here

volly818

go to your dealer and they can change it in the computer for a small fee. Maybe 20 bucks or so.