shocks usually fail over time and also by "bottoming out" frequently. by shortening the stroke of the shock with shorter springs...your shocks are prone to "bottom out" more frequently than on taller springs. this is the reason why shocks have "bump stops" to prevent such case. if the shock is sent back for warranty and case from research is because the shock failed from "bottoming" too much rather than normal wear and tear or defective failure...they have every reason to reject the warranty claim.