Yeah, I'd also like to know WHY this should be done as a matter of maintenance and not just if any codes are triggered. What does it fix or improve ? How can you tell you might need it, short of any codes ? Rough idling is one symptom mentioned, anything else ?
328i Sports Pkg, Hankook Ventus V12 (non-RFT)
. Wavetrac LSD + M3 diff fr bshgs
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. M3 subframe bushings + f&r sway bars + control arms. Meyle rear toe arms
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