One test I have seen people mention is if you suspect a certain part like the ball joint, spray it with WD-40 and see if the noise goes away for awhile (you have to get it under the boot of course). Do the parts one at a time so you will know which it was.

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra