hey guys i have been having probs with my Lincoln i had a lower ball joint replaced about 2 months ago because i herd a dry squeaking sound when i made small corrections dirving and sometimes when i hit a bump. now the same sound is back, i took the ls to the guy who did it the 1st time and now he cant tell if its the lower or upper ball joint. So then i went to Firestone and they cant tell wich one it is either but they did lube all joints struts n stuff on the side that is causing problems. What do u guys think should b my next step, go to a lincoln dealership and get charged about 100 dollars for a diag or just replace both ball joints