Stopped by NAPA yesterday and they had the WIX # on hand. 1955 wasn't getting any oil to the steeering unit and no brakes. Pulled the old filter and sure enough, there was a sustantial amount of ice in the filter can and element. Oil only has a few hours on it since the last change, but the tractor doesn't get run as hard as it used to either. Oil doesn't heat up much in the cold weather. Next time I am in town I'll pick up a couple of more. I expect I'll have to change at least one more filter before we get the moisture sorted out of the system. Thanks for the info guys.