What is the rear axle ratio of a 1990 Chevy Suburban?

There's no single answer to the rear axle ratio of a 1990 Chevy Suburban. The ratio varied depending on the engine, transmission, and options selected when the vehicle was built. A 1990 Suburban could have had several different axle ratios, commonly ranging from around 3.08 to 4.10. To find the specific ratio for a particular 1990 Suburban, you need to:

* Check the vehicle's specifications: Look for a sticker or tag inside the driver's side doorjamb, glove compartment, or owner's manual. This may list the axle ratio.

* Look at the differential: The axle ratio is stamped on a tag on the differential itself. You'll likely need to get under the vehicle to see this.

* Decode the VIN: While not directly providing the ratio, the VIN can sometimes be used to look up build information including axle ratio through online resources or a dealer.

Without knowing the specific vehicle's configuration, it's impossible to state the rear axle ratio definitively.