To find the rear axle ratio for a *specific* 1992 Chevy Silverado 2WD, you need to check one of these:
* The vehicle's build sheet (if available): This will list the axle ratio.
* The sticker on the driver's side doorjamb: This sometimes contains this information, though not always.
* The differential itself: The ratio is usually stamped on a tag on the differential housing. You'll need to get under the truck to check this. You can also look for markings on the ring gear.
* Your owner's manual (if you have it): It *might* list the axle ratio, but it's not guaranteed.
Without knowing the specific truck's configuration, it's impossible to give a definitive answer.
