I bought a set of 440 HD's for the bike 2 years ago and the left shock started to leak the oil out. I call progressive and they said the 440's have a lifetime warranty (with the purchase receipt). I called MAWonline and they faxed me my receipt from 2 years ago! (awesome) and I sent the shocks back to progressive for repair. A week later I got them back and they look brand new. It looks like they replaced everything except the springs. I couldn't be happier, they did a great job!