Finally installed M Factory LSD (pumpkin) bought during "Black Friday" sale. 3Hrs start to finish by a BMW Mechanic with lift and proper tools (and my help). Amazing what you have to drop to swap the diff. back belly pan, diff shield, triangular rear brace, Exhaust, heat shields, rear sub-frame, rear sway bar, and center driveline support. Then you can disconnect splined driveline (special spanner wrench required) and rear wheel 1/2 shafts. Pull mounting bolts and drop pumpkin down on a tranny jack. Install of new unit was straight forward reversing steps above. Dropping and reinstalling the pumpkin and exhaust is a 2 man job.
This is not something to attempt on jack stands.
Really didn't have a chance to fully evaluate on trip home. Definite improvement though no noise, clunks, or vibration. I will evaluate this spring. The car is put away for the rest of the winter
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2011 35i BMS High & Low side OCC, Custom tune, CDV delete, Eldor coils, ER Charge Pipe w/Tial BOV, ER Comp. FMIC, K&N drop in,40W LED Halo, LCI side markers, M-Factory LSD, NGK plugs, Racing Dynamics strut brace, Stubby, Windrestrictor