Hello all. I am looking at getting a 2009 Suburban LTZ but I just noticed that the brochure I have for the 2009's seems to indicate that only the 2wd models had the 5.3L engine with Active Fuel Management. The 4x4's just had a regular 5.3L. Can anyone confirm or deny this for me? I'd prefer to get the 4x4 for when I need it, but want ot save gase when I don't need 4wd. Thanks.