old versions that had zerk fittings. They have not used that type of ball joint for over 6-7 years and upgraded from those a long time ago to teflon SS hiem joins. If anything, they may squeak not knock. If they are knocking that usually means that the ball joint is excessively worn has excessive play and needs replacement and lubicating usually does not help. Contact Charles and I'm sure he can help you with solving that issue or upgrading you to the current hiem joints.
--Kwun
91 300zx Aztec Red Auto to 5-spd conversion TT 94 Supra White TT 6-Spd 93 RX7 R1 5-spd