This case contrasts manufacturing and design defects by analyzing each products liability theory in parallel. Plaintiff was injured when a truck hit him from behind due to its brake system falling apart. The truck was manufactured by the defendant motor corporation, but modified after-sale by the dealer. Due to the weight of the after-sale modification, it is possible that the accident would have occurred anyway as the installed brake system may have lacked sufficient braking power to stop the truck. However, at the time of purchase, the defendant motor corporation offered an alternative brake system that may have been powerful enough to stop the modified truck.