Yes. In my case, I had one very competent indie inspect the ball joints on my 91 300D, say they looked fine, only to find out later that they were the cause of my binding steering. More significantly I had a conversation with an indie in PA (when I was trying to figure out my steering issues) who knows the older Benzes INSIDE AND OUT. He relayed an instance where he visually inspected the ball joints on his daughter's car and one of them fell apart that week going down an alley! My point is that, apart from taking apart the suspension components, even a competent, experienced mechanic can miss bad ball joints.

In the OP's case, if he has ball joints that are now 25 years old, I say just go ahead and replace them....it's too significant a safety issue.

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14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 159k miles
06 E320 CDI "Rutherford", Black on Tan, 179k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver on Tan, 145k mi, wastegate conversion, ALDA delete

19 Honda CR-V EX 77k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife