The maximum towing capacity of a 2015 Chevrolet Suburban varies depending on the engine and configuration. It's not a single number. To find the exact towing capacity for a *specific* 2015 Suburban, you need to check the sticker on the driver's side doorjamb or the owner's manual. That sticker will list the maximum towing capacity for that particular vehicle.
Generally, the 2015 Suburban offered towing capacities ranging from approximately 8,300 lbs to 9,600 lbs, depending on the engine (5.3L or 6.2L V8) and whether it had the optional towing package.