The 2009 GMC Yukon lineup gains a new 6-speed automatic transmission, while the high-end Denali models gain power and new features. These large SUVs seat up to nine passengers and share their basic designs with the Chevrolet Tahoe and Suburban as well as the premium Cadillac Escalade. This report covers the Yukon and extended wheelbase Yukon XL. Compared to the Yukon, XL models are about 14 inches longer in wheelbase, 20 inches longer overall, and have nearly 30 cu ft more cargo volume. Yukon XL comes in half-ton 1500 and three-quarter-ton 2500 configurations.

Yukon and Yukon XL 1500 come in SLE, SLT, and luxury Denali models. The XL 2500 comes as the SLE or SLT. All are available with rear-wheel drive. SLE and SLT have optional full-time 4-wheel drive that can be left engaged on dry pavement and includes a low-range gear for off-roading. Denalis are available with all-wheel drive without low-range gearing. Standard on 2WD Yukon SLE is a 295-hp 4.8-liter V8 engine and 4-speed automatic transmission. All remaining Yukons and XLs have a 310-hp 5.3-liter V8. Optional on XL 1500 is a 366-hp 6.0-liter V8. XL 2500 versions have a 352-hp 6.0 V8. The 5.3- and 366-hp 6.0-liter engines have GM's Active Fuel Management cylinder deactivation. Yukon Denalis have a 403-hp 6.2-liter V8, an increase of 23 hp over 2008 models. All these Yukons have a 6-speed automatic transmission. 2008 versions equipped with the 5.3 V8 used a 4-speed automatic. The 6.2 V8 and versions of the 5.3 V8 can run on ethanol-blended E85 fuel. Maximum towing capacity for non-XL Yukons is 8500 lb. XL 1500 can tow up to 8100 lb, and XL 2500 up to 9600 lb.

Yukon Hybrids have a 6.0-liter V8 that pairs with an electric motor for 332 hp total. They can run on one or both of their power sources, depending on driving demand, and require no plug-in charging. Hybrids have a continuously variable automatic transmission (CVT). Hybrids can tow up to 6200 lb.

Available safety features include ABS, traction control, antiskid system, and curtain side airbags. Yukon XL models are now available with dual-screen DVD entertainment. Denali-exclusive updates for 2009 include the addition of heated and cooled front seats and a power tilt steering column.