My seems to be riding rougher (less comfortable) after i let 5 lbs of air from tires...I bought all new Bilstiens and the ride was nice this summer now this.I wonder why i lost my smooth ride?

 

Its cold out and the tires are stiffer as well as the rest of the components in your truck shocks, bushings, mounts, etc. Also the roads get heaved up alot in winter. Letting out a little air will get you better traction as well.