after 4 years, I would definatley be lookign for a new string, you dont want it to break on you, plus its probably pretty stretched by now. I just bought one myself. anybody with a bow press can install it for you as long as you get the right length, make sure you get a new buss cable to while your at it. By the way I bought a Prostring, and I like it alot. Its a great string and it wasnt expensive. heres their site http://www.prostring.com/