I went with M factory. The E89 does have a welded ring. They have the capability to rebuild the pumpkin and put a new ring on their helical style LSD units. The only other company I found in the states will machine off the existing ring and reuse it is VAC in PA. Email Stephen. He is a pleasure to deal with. Tell him we talked.
syeh@teammfactory.com I am extremely pleased.
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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