2004-2007 Cadillac CTS-V General Discussion Discussion, Mods ??? in Cadillac CTS-V Series Forum - 2004 - 2007; Thinking abt changing shifter and adding cold air intake, Also any way to tell if rear diff in my car ...
You cannot identify which differential you have by VIN, but if it original to the car it is an earlier version. The first significantly improved units came with the 2006 model year. The most recent version came out as a replacement part in 2008 even though there were no CTS-Vs produced that year. The part number off of the differential can tell you which one you have and there are visible differences. http://www.cadillacforums.com/forums...rear-diff.html
The cold air intakes add sound which some folks like, but do not expect a significant power or fuel economy gain.
If you really want to do a CAI look into the trashcan method! I found it and some of the best 50 dollars I spent! Plus it gave me something to do. Like Darkman said I don't think it did a lot but with future mods I plan on doing it will help later on down the road!
I find it rather odd about cold air intakes. People always bash the volant one and when I got mine, I actually noticed a difference between the intake and stock. And it was a positive difference. As far as gas mileage goes I don't know cuz 2weeks later I installed longtubes n exhaust. I'm pretty happy with the stock shifter after I got used to it and it bein the only standard car I drive on a normal basis but I'm sure that will change when I bite the bullet and finally decide to get a short throw