Originally Posted by Stretch

With reference to the Mercedes UJs => there was mention that knocking them out a little bit - squirting oil (I think) - and then knocking them back fixes the notchiness problem. I haven't tried this myself yet (too busy moving house and sofa surfing at the moment) so I'm not sure if this works. I can find a link to this if needed...

...if I remember correctly the basic message was that the needle bearings within get rusty and just need a bit of help...