There really seems to be some confusion regarding this. Perhaps most of the confusion is with my dealer! When I "built" my machine I included the $99 upgrade to the front suspension, but the dealer called and said that the newer X900 machines come with the same heavy duty front suspension that the X1100 series comes with and I didn't need the upgrade. I took his word for it. Then when I put the Boss V-Plow on I questioned the decision and ordered the heavy duty springs I had originally asked to be put on. Turns out the springs I ordered are the same as the ones on it! Now I am really confused!!