How do you guys tell what gears are in a 2002 Cummins Auto and if its posi. Thanks.

-Dustin-

 

There should be a sticker inside your glove box. It will give you all sorts of vehicle specifics

 

Ask a dealer in the service department to run your vin. See if he will give you a copy of the print out.

Dave

 

Jack up the rear end and turn a tire forward....if they both turn forward you have a LS. If one goes forward and the other goes reverse you don't. There's also a metal tag held in place by the diff cover bolts that should tell you if its still there. THis of course if the glove box info isn't there but it should be.

 

Jack up the rear like he said. Make a chalk mark on the bottom of one tire. Make one on the bottom of the drive shaft. Now put the trans in neutral and turn the drivshaft by hand. Watch the chalk marks and see how many driveshaft revolutions it takes to bring the tire one complete revolution. This will give you a ballpark idea.
Slightly more than 4 turns = 4:10
3 1/2 turns = 3:54
3 3/4 turns = 3:73

Another way, if you want to do it, is take the cover off the differential. Count the teeth on the ring gear and divide that by the number of teeth on the pinion gear. The result will be your gear ratio. I did this on an old chevy. The ring gear had 37 teeth and the pinion had 9. 37 divided by 9 gave me 4.11. It was a 4:11 rear end.

 

A 4.10 truck will tack 2000 rpm at 60 mph and a 3.55 will be around 1700. and then put one foot on the fat pedal and the onther on the skinny one, and press on both at the same time, if smoke comes off both tires, it's a posi. if only one, then not, or it's not work right.

 

I like the way you think!!

WR

 

well its by far the easiest and most enjoyable

 

I second that statement