* 4.8L V8: This was a common engine choice.
* 5.3L V8: Also a frequently offered engine.
* 6.0L V8: This was available, but less common than the 4.8L and 5.3L.
Therefore, there's no single answer to the engine size. You need to check the vehicle's documentation (like the title or owner's manual) or the sticker on the driver's side doorjamb to determine the specific engine size of a particular 2001 GMC Yukon.