My wife’s 2002 Mercedes ML320 has about 125K miles on it. Our mechanic recently told her it needs new ball joints. When I drive it I can’t feel or hear anything unusual. How can a totally non-mechanical type like me tell for myself when the ball joints are suspect?
You really need to trust your mechanic. Since you post the question, you should get a second opinion from a good mechanic, not a Midas type chain.
A small amount of play in the ball joints when the car is on the hoist is acceptable. One automotive chain uses this play as a scare tactic to sell unneeded ball joints.