[cooperino]

Hi! Welcome to OCC

So, If I were you. I would take the deck off the tractor. Then I would take the deck belt off. I would then spin each Shaft and pulley by hand checking to see if any feel tight. I would also flip the deck over and give it a good cleaning and probably a coat of paint. If all seems okay with the deck itself I would start looking at the drive belt. It could be worn and or slipping. The things I mentioned to do with the deck plus greasing any zerks should be routine yearly or twice yearly maintenance anyway.