Yes it does have 55 series tires on it. That was why I got the tuner first so I could fix the speedo and shift points. I have thought about lowering it but my Only concern is I have a couple 4wheelers and stuff that I will need to tow every now and then so I don't wanna go to low. I was thinking maybe lightning spec bilsteins and 2 in in the rear to level her out a bit. Haven't done enough reading up on the suspension stuff though to know what would work best. The tires are still pretty new as well so I don't wanna replace them just yet. I'm sure after the engine up grades a new set of rears will be in my immediate future.