In Calif. , they tax you on everything. One tax is on the un-laden weight of your truck. When I got my permanent registration for my truck, it said that my '01. 5,QC,SB,2WD weighed in at 6130lbs. I went to a truck scale and got the truck weight certified. It only weighed in at 5750lbs. Weighing at under 6000lbs makes my weight fees $50 dollars cheaper per year! $5 dollar weight certificate saved me $$$$$! Don't know about you guys in other states but maybe worth a check. FYI