One problem related to ball joint has been reported for the 1998 Lexus GS300. The most recently reported issues are listed below.
Was on the freeway driving about 60 miles per hour, hit a pot hole, car dropped apparently the ball joint broke on the right side. But this happened on the left side a few months ago in December. That time I was not on the freeway. After researching on line I saw that previous models had been recalled for this problem but not the 1998. After the incident in December and the damage was corrected, I took my car to my mechanic and he checked it out made some adjustments, then it happens again. I'm afraid someone could get killed, luckily I didn't, especially the second time when I was on the freeway. Why would this happen, I always thought a Lexus was a very dependable car.