The main reason for not hitting a driver as long as you should is hitting down on the ball. IF you hit your 3 iron well, you are most likely hitting down on the ball. This is fine with an iron, but not with a driver. I recommend that you see a good instructor and have him look at your swing plane with the driver. My guess is that your swing is too up-right. You have to sweep the ball off the tee with your driver if you want to get any distance with the club. I tend to swing too up-right with my driver, and as I am getting my swing improved to sweep the ball more, my distance is increasing all the time. Try it and I think you will see an improvement before long. A second tip would be to try a driver with more loft, maybe 11-12 degrees.Good luck with that driver.