The Yukon XL 2500 seats six to nine people and this heavy-duty version can tow up to 9700 pounds. It is rated for three-quarter ton and has truck tires with a heavier suspension using leaf springs. The standard 5.3-liter V8 offers excellent horsepower and torque. An optional 6.0-liter V8 for the Yukon delivers more towing power. The Denali trim has its own engine, a 6.2-liter V8 based on the Corvette's 7.0-liter, making 380 horsepower. The Yukon XL comes in two-wheel drive or four-wheel drive. Safety equipment on all models includes dual frontal airbags, four-wheel-disc anti-lock brakes with electronic proportioning, and StabiliTrak.The GMC Yukon XL 1500 is all new for 2007.