how to find axle ratio??

[YBSTUK]

when looking at used suburbans, how does one know the axle ratio?

is it in the VIN number somewhere, like the engine?

do i have to crawl under the back, and inspect the rear end's tag?

is there a resource on the web that allows you to plug in the VIN number, and it gives you all the info on that particular truck? (i think they can do this at the dealer).

ANY help would be great! thanks!

bryan

[Fireplug]

Get the RPO code numbers. It will be a sticker with a bunch of code numbers on it. That that to a dealer and they can tell you everything that is on that truck. Not sure where yours is ,glove box? look around

[syd4998]

It should be in the glove box. Like mine is GT4 which is a 3.73

[Eggert]

Hi,
the available rear axle ratios depend on your model and engine size.
The higher the number, the faster the engine turns.
Better power and towing, slightly less gas mileage.
GT4=3.73, GT5=4.10, GU4=3.08, GU6=3.42.
Are you looking at new body style or old body style?
What engine size? How much towing capacity?

For Example, in the 2001 Yukon XL K2500:
The 6.0 liter with the 4.10 tows 10,000lbs.
The 8.1 liter with the 3.73 tows 10,000lbs.
The 8.1 liter with the 4.10 tows 12,000lbs.
Take care, Eggert