Hi Ken,
Since your S/N is 447 away from mine (also an L3), 1994-1995 would be my guess - but a dealer can contact Kubota and get the actual date the tractor was first sold at retail. The "year" of the tractor is determined by the sale date. Perhaps one of our dealer members will post the original sale date for you.
Sorry your other thread on the L4350 got off-course. You had asked about tire sizes - there is a very good article on this at TractorSmart - look under the Info Tab. Take care, DickB
Any help on the serial number? By the way I've torn down front end and have right front kingpin assembly sitting on the workbench. I'm waiting on new seal to arrive. Hopefully I'll have it in a few days and I can get it up and running.
Ken
Here is the ball bearing, shaft support, and snap ring all cleaned up and ready to install. Both o-rings were gone from shaft support and had to be replaced.
I removed bevel gear case and put it up on the bench. The upper race for the thrust bearing is a press fit. I heated it a little so it would release from the shaft and slide off. I removed old seal and cleaned up shaft with scotch brite pad. I drove on new seal with an old enfamil can I keep bolts in the shop. It was just the right size. This pic is the bevel gear case upside down on table with new seal, and upper thrust bearing race reinstalled.