OnStar is NOT why Nav is not available...
NAV is an available option on Many (but not all) GM cars even with OnStar. That said, there is probably some other reason why there is no Nav option (They liked the dash design as is and didnt want to clutter it with a screen there? who knows....). I don't know what it is, but i probably wouldn't have gotten it anyway.
I'm Brick Tamland. People seem to like me because I am polite and I am rarely late. I like to eat ice cream and I really enjoy a nice pair of slacks. Years later, a doctor will tell me that I have an I.Q. of 48 and am what some people call mentally retarded.
2010 Chevrolet Camaro SS - Daily Driver
1996 GMC Sierra 2500 SLT - Tow Vehicle
1993 Volkswagen Fox - Race Car (yes seriously)
"Like" my race team on Facebook: http://www.facebook.com/farfrumwinnin