It depends if it is an OHV(pushrod motor) or a s.o.h.c./d.o.h.c. motor. Ohv engines can have a timing chain set that allow for adjustment, to be installed. You can also install crank keyways that adjust the timing by moving the crank cam gear the required degree/s. Overhead cam engines can have cam gears installed that allow for cam adjustments.
The 2001 Chevrolet Corvette has overhead valves (OHV).
The 2012 GMC Savana has overhead valves (OHV).
The 2006 Chevrolet Tahoe has overhead valves (OHV).
The 2012 Chevrolet Suburban has overhead valves (OHV).
The 2003 GMC Yukon has overhead valves (OHV).
The 2007 Chevrolet Corvette has overhead valves (OHV).
The 2005 Chevrolet Equinox has overhead valves (OHV).
The 2008 GMC Yukon has overhead valves (OHV).
The 2004 GMC Yukon has overhead valves (OHV).
The 2015 Cadillac Escalade has overhead valves (OHV).
The 2009 GMC Yukon has overhead valves (OHV).