I have always thought that my rear end was a 4:10 but a friend of mine said that he saw something online and mine was lower than that, im sure you guys can tell me what i have.

2002 3500 2wd 5speed and at 70mph it runs just a hair under 2400RPM's

 

It should be printed on the sticker, inside the glove compartment.

 

4.10 was the lowest offered in a SRW as far as I know.

I have 3.55's and at 70 I am about 2100 so this sounds about right.

If you are skeptical jack it up and turn the tire one revolution while counting the driveshaft rev's and you'll be close to your ratio if its not stock.

 

Try a tire/gear calculator. There's lots of them online. And it sounds like you have 4.10's.

 

yup 4:10's didnt know that it was in the glove box thanks