You can try suing the store and the pump's manufacturer, and if you can prove that one or both of them was at-fault in causing the damage (for example, that the pump was manufactured or designed improperly; or that the store sold you a pump that had been returned to them and which may have already been damaged) you could recover the repair costs. Be warned, however, that a lawsuit like this can be expensive, since you need expert testimony (e.g. from an engineer or experienced mechanic) about the cause of the pump's failure and how it damaged your truck, and such experts generally charge for their time; you also effectively need an attorney, because a lawsuit like this is not an easy one for a non-lawyer to bring. You could end up spending as much or more on the lawsuit as you would get back.You may wish to first contact the manufacturer with what happened; they may be willing to pay something to you to avoid the chance of litigation.