As specified in Technical Bulletin TB 84-01, early 928s were fitted with aluminum lower ball-joints which should be upgraded to steel replacements.
This is an important upgrade because the aluminum LBJ's will fatigue and fail. I'm shocked at how many early 928s still have their original aluminum ones!
TB 84-01 reads from September 1983; 92 ES 860404, which translates to MY84 up to VIN WP0JB092XES860404. Physically check your 928 before ordering parts. The TB specifies more parts than what is absolutely needed. For safe replacement, this is what I recommend to service both sides:
- (2) Lower ball-joint, steel - P/N 92834104912
- (2) Eccentric, camber/caster - P/N 92834146600
You can reuse two of the original 26mm diameter camber eccentrics, P/N 92834146601.
Also consider reusing the original mounting brackets, P/N 92834109103 & 92834109203.
The only difference is the threaded studs are longer and will protrude farther. Note: Steel LBJ P/N 92834104912 was superseded to P/N 92834104914. This applies to 78-86 up to VIN WP0JB092XGS860999.