If its quiet and not leaking I would put it up in the air and check the end play of the axles also have a buddy grab one tire and you the other and turn in opposite directions a good sure grip should put up quite a battle close to 200lbs. If thats all good suck the gear lube out with a pump and refill it and add conditioner. If it ait broke don't fix it! If it fails pull the axles pull the center section and have it all inspected if you don't know how.