Parked my cub cadet after mowing the lawn the last time. Went out today to mow again and it won't move either forward or backwards. It acts like it is locked up, I released the transmission lever to push it back by hand, but it was still locked up.. Jacked up the rear end and the tires move freely, but, when moving the tires by hand, one will go one direction and the other will go the opposite direction. Anyone know what can be wrong with it? When trying to move with the engine running, the transmission makes a whining noise, like it's trying to pull 1000 lbs .