Well I traded my NNBS for a 06 TBSS about 2 weeks ago.. So far I love the power! I'm going to miss my truck but I think I did a pretty fair trade. The trailblazer has been played with. It has efans, cai, magnaflow cat back, and a catch can I know for sure.. And I think it may have a UD pulley. Is there any way I can measure the pulley to see if it's UD? Looks to be maybe a little smaller or same size as waterpump pulley.