The most common failure in these old radios is the vibrator. However there are capacitors which should be replaced, namely all the wax covered paper ones and the electrolytics in the silver can. I don't think this radio would ever have static from dirty bearings because the tuning mechanism is not a variable capacitor but an array of moving ferrite cores inside coils. The best approach is to replace all the above parts before trying to troubleshoot the radio. I have repaired numerous radios where the old tubes test in the good region and perform correctly.
