See also:

Add-on Electrical Equipment
The OnStar system is integrated into the electrical architecture of the vehicle. Do not add any electrical equipment. See Add-On Electrical Equipment on page 9‑64. Added electrical equipment ...

Front Axle
The front axle engages and disengages automatically when you shift the transfer case. Some delay for the axle to engage or disengage is normal. ...

Safety
The National Highway Traffic Safety Administration gave the 2007 Yukon a five-star frontal crash-test rating; it hasn't done a side-impact test as of this writing. Rollover ratings were listed at ...