Truck Lowering Questions?

I own a 2007 GMC Sierra 1500 Regular cab 6ft bed New Body Style. I have been looking at lowering kits that are a 3"/5" and see in parts list that shocks not included. Now does that mean i need to get a different set of shocks in order for the drop to work? or can I use the stock ones for the time being?  

I happen to find the answer. Yes you can use your stock shocks sometimes. depending on the drop. but in time they will give out which will require you buy new ones. But DJM shocks only cost about another 60 bucks a pair to prevent from blowing out stock one and damaging your truck. Quick note. I am surprised on how many views there are on these post but with next to no comments kind of sad.  

Ya, was just about to say the same thing about the stocks.