Kris,
You're wise to do the repair yourself. Benchmade is good, they'll ship parts to you and they'll also fix the knife if you send it in, BUT..... it costs shipping both ways, insurance, and most importantly at least 3 weeks time, more like 4. I know... I have experience with sending and receiving knives from them. They're honorable but busy.
All you need is a torx set, probably a #10 for the pivot and smaller one for the frame screws. A good place to get the Torx set is at Home Depot... I have one that costs about $6 and has all the sizes needed to work on knives.
Husky HD-74502 V. It has sizes #4 through #10 and a #15. You can look it up on the internet to see what it looks like if you want one of those.
The Axis springs are
ridiculously simple to remove and install. When you get the knife apart, you'll see what I mean. I recommend NOT taking it apart until your new springs arrive (so everything will be fresh in your mind as you do it). Take care that you set the washers apart in a manner that you can remember to put them back in exactly as they came out.
It's so easy it will surprise you. Good luck.
ON EDIT: With some exceptions, folding knives are simple devices... they're just one step up from fixed blades!!
Benchmade's policy of voiding the warranty because the knife was taken apart worries alot of people. The biggest problem is the washers. They're designed to go in one way and on one side only. In alot of knives, one washer is larger in diameter and thicker than the other, usually on the side that must resist pressure from the lock or bearing. And in some knives, there are more than 1 washer on each side, each designed to go in a certain way. So...take care when removing and replacing the washers. I don;t worry about their warranty policy when it comes to taking the knife apart. The biggest concern here is that you'll take it apart to clean it or something and then later a different problem will arise and the warranty will be voided. Don;t worry about that, their warranty is to prevent people taking the knife apart and then not getting it back together correctly, then complaining because it's not smooth, or the blade is off-center in the frame, etc.