1987 300D Turbo

I just heard this clunking noise during acceleration from a standing start. Not right away, though only at about 20 mph and then nothing. Some swaying also at cruise. Very worried, up on the lift and nothing unusual to the eye.

Then I grabbed each rear wheel. Left OK. Right is loose!

Lugs where tight so could this be a wheel bearing or an axle shaft or something else?

Car is unsafe to drive now, so any help would be greatly appreciated. I am looking on the maintenance CD now.

__________________
Gerry

59 Ranchero
83 928 Euro S
84 928 Euro S
87 300D Turbo-Frybrid "WVO, Tastes Great - Less Filling"
90 750 IL
91 560 SEL