I have been in contact with a vendor and he assures me that there shark fin antenna will work with my 2011 SRX. This reply was to my sending numerous pictures of my SRX antenna with measurements and specifications to the vendor. As you can see from the reply below, the vendor assures that the XM/Onstar/GPS signals will not be interfered with but, AM/FM station reception may be reduced. As I never listen to AM/FM anymore I don't see this as major issue. The vendor will color match the Shark Fin Antenna to my SRX color (Platinum Ice Metallic). I will let everyone know just how this turns out as I just placed my order a few minutes ago. Pricing is $69 plus $12 for shipping. See below
Thank you for your email.
Our pre-released Mark II VG shark fin antenna is compatible with your 2011 Cadillac SRX. For more information, pictures and how to order, please see the email below.
This new shark fin antenna was developed specifically for vehicles that have an AM/FM rear-roof whip antenna and a Sirius/XM/OnStar/GPS chip-set antenna integrated into the larger antenna base. Our Mark II antenna will allow you to replace the whip portion of your AM/FM antenna and cover the entire large antenna base on your roof to give it a clean look. Installing this antenna will not hinder the operation of your Sirius/XM/OnStar/GPS chip-set antennas that are integrated into your antenna base, however, it may be possible to notice a slight drop in reception in AM/FM especially when listening to stations that are located further away or stations that have weaker signals.