I just rebuilt on of my spindles last month and the bearings were Timken tapered roller bearings with seperate press in seals in the housings. I give them 6-7 pumps on the grease gun about once a month.
OM thanks for that. I haven't needed to pull any apart on my 2544 yet thankfully. I did just rebuild all 3 spindles on my 30yr/old Case 38" deck. Those particular ones were 'sealed' non-greasable and lasted 30yrs! They still rolled decent, but NOISY. 6 new bearings from eBay mailed to the house for under $30.