My 86 535i has a squeaking noise up front when I turn the wheels. Looking underneath, rubber bushings look ok. Tried to get alignment, but mechanic says I need tie rod ends replacing due to wear ($200 installed). Could this be making the noise? Doubt it, it is probably your upper strut bearings. Suspension seems good, but noticed broken rubber piece at top of bottom section of strut. To fix this do I have to replace strut, or can I buy the O ring and drop it on the strut? This is the upper strut bearing. You can purchase it separately and install it without having to replace any other parts. Does strut replacement take a spring compressor?
If you have stock springs yes Rob M535i SIG Chief Technical Advisor www.m535i.org