How do I figure out which gear ratio I have. I can't seem to find it on the invoice anywhere.

 

Check the info panel in your glove box. Mine was attached to the box door and listed the various specs. If you have a newer manual 2500, you have 3.93 gears because the 6spd ratios balance it out to an auto with 4.10 gears.

 

if you have an 06 the build sticker in the glove box is missing.

Shaun has it with the G56 only having 3.73's, but the auto with 3.73's will run around 1900 or so RPM, with 4.10's you'll be turning around 2200RPM at 70mph

 

Why did I type 3.93? Brain can't keep up with the fingers.

 

I saw it at 3.73 myself

dislexia kicking in good today[:@]

 

I have a 06-3500 DC-6 spd.. I was told when I got it that it had 3.73 gears. But now I think it has 4.10 because I am runing about 2200 @ 70. Drew said that was 4.10 right ?

 

no, the G56 has shorter gears so when you are in 6th you are running a .79, my NV5600 is running a .76(I think) so when it comes down to it my NV5600 with 4.10's is turning the same RPM's as your G56 with 3.73's

 

If you don't have the sticker in the glovebox, shouldn't it say inside the door if I'm not mistaken?

 

for some reason the 06's done even list the diff ratio on the window sticker

 

Same problem with 06 and my service mgr used last 6 0r 8 numbers from the vin code to do look up. If it has 4.10 it would be an extra on window sticker if equiped with auto.