bsubvrsv said:52390-SG0-043 ARM, R. RR. (UPPER) 2 1989 Acura LEGEND 99.40 79.52
I don't know if it's replaceable or not. I don't think so, from what I've been able to find. The ones on my 87 coupe need to be replaced. Let me know if you find out different.
masupra said:You need to buy the whole arm, which comes with the ball joint. $99 sounds to be pretty good price -- I bought mine from ahmotor.com for $140 each. The rear uppper arms of our cars are highly stressed, so I would buy geniune Honda if I were you.
Mine was rusted, too. After trying two hours with a drill and dremel, I gave up and brought it to my mechanic. The guy use a torch to to melt the metal stud and removed the old one.