If I were you, I would have someone look at your impact position. Sometimes we are swatters and don't even know it until someone points it out. I am guessing from the post that you are athletic and can swing the club at a decent clip say 95-105 mph and that you are playing with a stiff shaft driver. How is your ball flight with your
irons, are you getting high trajectory there as well with shorter distance?
If you are all the above, have a look a Greg or Jeff Manns website. they have some great tips on stopping this distance robber.
I speak from experience. I went to a lesson and learned that my club was getting ahead of my hands before impact. With a few tips and a lot of practice I have cured myself and I have picked up A LOT of distance particularly with my
irons. My driver is 50 yards longer!!! I don't mean to come across as bragging, what I mean to point out is that getting the basics nailed down will help you acheive the distance that you are fully capable of.