I definitely would service your motor. Cleaning and fresh lube should ready it for many more years of service. Even if the bearings are noisy, with fresh grease they may last for years. I once had a postwar XXX with a noisy rear bearing that I chose not to replace because it still turned smoothly. After servicing, it ran fine and never got noisier.

Just today I serviced a prewar XXX (475-watt) motor. The all-metal Lux motors are easy to work on. Before doing anything to mine, I test-ran it and found that the bearings were quiet and had a normal wind down. I flushed them with CRC QD Electronic Cleaner spray, and tomorrow I'll repack them and reassemble the motor for use in my current XXX. It previously had its motor replaced with a late 535-watt motor, so I won't lose any sleep over installing the motor I want it to have.

If you use CRC QD cleaner, please note that it cleans really well but it evaporates quickly and will chill metal parts enough to cause condensation from the air. I use the warm exhaust from another vac to bring the parts back to room temperature and prevent rust in the bearings until I can get them repacked.

Joel