What is the towing capacity of 1999 gmc sierra 3500 crew cab 4 x 4?

The towing capacity of a 1999 GMC Sierra 3500 Crew Cab 4x4 depends heavily on several factors, including the engine, transmission, and axle ratio. There's no single answer.

To find the *exact* towing capacity for your specific truck, you need to:

* Check the sticker: Look for a sticker on the driver's side doorjamb or in the glove compartment. This sticker will list the maximum towing capacity for your specific vehicle configuration.

* Consult the owner's manual: Your owner's manual will also specify the towing capacity based on your truck's options.

Without knowing the specific engine and other options of your 1999 GMC Sierra 3500, I cannot give you a definitive towing capacity. However, expect a range generally in the 12,000 to 16,000 lb range, but that's just a broad estimate and could be significantly higher or lower depending on your truck's configuration. Always rely on the information found on your vehicle's documentation.