Steering problem with Mazda Tribute


My 2003 Mazda Tribute’s power steering started failing when I turned sharply (to the limit) at low low speed, i.e when there is a lot of resistance. I took it to the dealer and he said the pump should be replaced. They replaced the pump and now say they have to replace the rack as well becuase some wheel in the pump had falled apart and pieces fell into the rack and damgaed that. I am not able to picture this and wonder if it makes any sense. It sure makes a lot of cents for the repair shop. Megan in Baltimore