The rear wheel bearings aren't as simple as you might expect - have a look at these threads

PeachPartsWiki: Replacing the Rear Wheel Bearings

http://www.peachparts.com/shopforum/diesel-discussion/277341-w123-rear-wheel-bearing-removal-help-needed.html

If you have a dial gauge - DTI - clock gauge you can measure the bearing play. But to do that you should remove the axle...

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!