I have a 2003 Suburban with the 5.3. anytime we take a right or left turn the rear end locks. i understand its supposed to lock when one of the wheels spin but when your going around a turn the inside wheel is supposed to free wheel. we still have the window sticker and its got the locker option on it for like $225 dollars more. we took the rear cover off and found that some of the spider gears are chewed up. does anyone know where i can start looking to get parts to rebuild the locker?