Mechanic Q: It can't need rebuilt can it??

Truck makes noise in 1st and 3rd gear. It is an 07 e250 SD and has 28,000 miles on it. I baby it while driving but I do haul often. It first happend while slowing down. It was only 1st gear making noise but now it's 3rd too. It sounds like something is rubbing. At first I thought a stck or bag was caught in my wheel well but realized it was the tranny.