The 2013 GMC Yukon has 16 valves.
The 2013 GMC Acadia has 24 valves.
The 2013 GMC Savana has 16 valves.
The 2013 GMC Terrain has 16 valves.
The 2013 GMC Sierra-3500HD has 16 valves.
The 2013 GMC Yukon-Hybrid has 16 valves.
The 2013 GMC Yukon-XL has 16 valves.
The 2013 GMC Savana-Cargo has 12 valves.
The 2013 GMC Sierra-2500HD has 16 valves.
The 2013 GMC Sierra-1500-Hybrid has 16 valves.
The 2013 GMC Yukon has overhead valves (OHV).
The 2013 GMC Savana has overhead valves (OHV).