BLACKLINE PROFESSIONAL TRACTION SYSTEMS. Helical Gear Limited Slip Differential. SUITABLE FOR BMW 188K MEDIUM CASE 10 BOLT CROWN WHEEL DIFFS. The 188K differential among others (168,188,188L, 210 etc) are most commonly used in 6 cylinder engine versions of the following models. BMW E82 123d Auto / 125i / 128i Manual / 135i Auto. BMW E87 118d Auto / 120d Auto 03/2007-09/2008 / 123d Auto / 130i /. BMW E46 318d Auto / 320i Manual with 188L Casing / 323i Auto / 325i / 325ti / 325xi / 328i 3.46:1 ratio / 330i Auto. BMW E90 320d Auto with 7591017 Diff / 320d Manual with 7591074 Diff / 320i with 188K Casing / 325i Auto / 328i Auto / 325i Manual with 7591015 Diff / 328xi Manual / 330i / 335i Auto with 7572055 Diff / 335xi Auto /. BMW E92 320d Auto with 7591017 Diff / 325i Auto / 328i / 325i Manual with 7529109 & 7591015 Diff / 330i / 335i Auto with 7572055 Diff / 335xi Auto /. BMW E39 520i Manual / 523i. BMW E60 520d Auto / 520i / 525i Auto / 525i SMG / 530i Auto / 535i Auto / 535xi Auto. BMW F10 535i Auto / 535i Manual. BMW E38 728i Auto. BMW F01 740i – Check Diff Fitted / 740li – Check Diff Fitted. BMW E83 2.0d Auto Rear / 3.0i Manual Rear. BMW E53 3.0i Manual Rear Diff / 4.4i Auto Rear Diff / 4.6is Auto Rear Diff. BMW E70 3.0d Auto Rear. BMW E85 Alpina Roadster S 3.4 / 2.5i / 3.0si / 2.5si SMG / 3.0i Auto. BMW E89 2.3i S Drive / 3.0i S Drive. 168,188,188L, 210. Differentials – also available in our shop. Blackline Helical LSD’s – How They Work. The Blackline helical LSD’s are torque biasing, that is they distribute torque between the wheels, loading more torque towards the wheel with the best traction thus improving performance and driveabitily. Especially in low grip situations. The helical gearing manages the distribution of friction within the LSD. When torque is applied to the helical gear system it creates force that pushes the gear into the differential body, thus creating friction. Increases of torque, increases the thrust force directly proportional to the amount of torque. This allows the Blackline LSD to cope with considerable traction imbalance even under heavy power conditions, as would be the case on exiting a powered up corner. But at low torque conditions the LSD can differentiate quietly and smoothly, thus making the differential very suitable for normal road driving. The Blackline LSD uses the popular parallel axis helical geared configuration optimised for even load distribution. They are designed with a torque bias of 5:1 this means that if one wheel loses traction then the wheel with the most grip can receive five times as much torque as the wheel that is slipping. However, five times zero is still zero, so all these helical LSD’s work best when both wheels are’planted’ and some traction is still available on the slipping wheel. In practice this is rarely a problem as there is always some’drag’ on the slipping wheel, however some drivers expertly use left foot braking to partially lock the spinning wheel. Helical LSD’s work especially well when combined with modern anti-lock braking systems. Applies equal rotational speed to both wheels. Distributes torque according to available traction. Minimum servicing compared to plate type LSD’s. Controlled power on launches and drifting slides. Optimum gear tooth design and oil distribution. Gears and Body Manufactured from 8620 material. Direct replacement for stock differential. This is a Torque Biasing Helical Gear LSD. These are generally regarded as a nicer road LSD as they have little side effects during normal driving (unlike plate type LSD’s that constantly resist differing wheels speeds during cornering) They do not require a special oil. We recommend that the axle oil is changed after the first 500 miles as initially they can create swarf – this is normal and will reduce with use. (NOTE: This is NOT a plate type, viscous coupling or clutch pack LSD). Assembled Differential Unit ONLY. Bearings, gears, gaskets/seals etc are NOT included. No instructions are included. Questions: We are happy to do our best to answer sensible, genuine questions during our normal office hours (Mon-Fri 09:30-17:30), however please note we do not have intimate knowledge of all makes & models or have personal experience of fitting/using all our products. Products only fit models stated (if products fit other models its in our favour to say so)! Products listed as universal fitment are not designed for any one model.