What is the tow capacity of a GMC Sierra 2005 crew cab 4x4 with 5.3 and 3.73 differential?

The towing capacity of a 2005 GMC Sierra 2500HD Crew Cab 4x4 with a 5.3L engine and 3.73 differential is not consistently reported across sources and depends on other factors. The 5.3L engine was typically found in the 1500 series, not the 2500HD, which had heavier-duty powerplants. A 1500 with that engine and configuration would have a significantly lower towing capacity than a 2500HD.

To find the exact towing capacity, you must consult the sticker on the driver's side doorjamb of your *specific* vehicle. This sticker provides the manufacturer's recommended maximum towing capacity based on the exact configuration of your truck including options like transmission, axle ratio, and installed equipment. Online sources offer general ranges, but they aren't a substitute for the information on your vehicle's sticker.