Bmw E30 E28 Zf 3.73:1 Clutch-type 188mm Limited Slip Differential Lsd Akg 75d on 2040-parts.com

BMW e30 e28 188mm ZF Clutch-Type Limited Slip Differential LSD 3.73:1 with AKG Motorsports 75D Bushing

BMW e30 e28 ZF 3.73:1 Limited Slip Differential (LSD) "medium case" 188mm with double-clutch discs for BMW factory 25% lock-up and AKG Motorsports 75D bushing.  75D hardness is similar to delrin, and both of these materials are the stiffest you can install below solid aluminum.  FOR PROPER OPERATION, IT IS HIGHLY ADVISED THAT YOU HAVE, OR ARE GOING TO INSTALL, SIMILAR STIFFNESS/HARDNESS: (i) rear subframe bushings (RSB's); AND (ii) rear trailing arm bushings (RTAB's).  Otherwise, when you drop your clutch you will actually feel the rear subframe shift--which is also connected to the LSD--under drivetrain load as a result of rear bushing deflection. 

This results in unwanted torque-steer due to rear bushing deflection (as opposed to traditional torque-steer caused by the release of massive drivetrain power such as dropping the clutch with a turbo at full-boost) as the LSD and rear CV axles are locked-up by forward tire rotation while the RSB's and RTAB's are forced in the opposite or reverse direction.  The softer/worn your RSB's and RTAB's are, the more unnecessary rear-wheel-steering you will encounter.  

Also advised are the use of stiffer: (i) rear shock mounts (poly RSM's such as Ground Control, Vorshlag, AKG, Condor, etc.); (ii) shocks (Bilstein Sport, Koni Sport 1994-04 Ford Mustang (top and/or external-DA rebound/compression, 12mm RSM shaft, THESE ARE THE BEST!), or Koni Sport BMW e30 (bottom-SA rebound, 10mm RSM shaft), etc.); and (iii) springs (IE3, H&R Race, etc.). 

Use of lesser quality parts then those mentioned above WILL result in LESS THAN SATISFACTORY RESULTS!  Of course the trade-off for such a non-compliant rear end bushing such as the 75D one installed in this LSD is added road noise, more vibration, and less comfort.   

Percentage of lock-up can be changed with addition of extra clutch discs (3 discs = 40% lock, 4 discs= 75% lock), which are not included in this sale.  (Yes, I'm fully aware of the 5-disc mod, but that expensive mod is usually only done by professional race teams :-).  You can also change the ramp angle of the ring-and-pinion gears to change lock-up characteristics from less-predictable factory "on-off" LSD clutch disc engagement to a more-predictable "progressive" engagement.

Removed from 1989 e30 325iS with 124k miles on it.  In very-good used condition.  Get better cornering grip by preventing inside wheel-spin with this 25% double-clutch disc LSD.      

BMW part # 331012111961.  If you are unsure as to fitment, please consult your local BMW dealer as fitment is buyer's responsibility.

Please also do not purchase this item if you are unfamiliar with determining whether this item is functional or not, as some current buyer's of items are definately incapable of making that determination, or timely seeking those who are. YES, I WILL KEEP THIS ITEM RATHER THAN SELLING TO YOU NOOBS (re-seller middlemen, general mechanics--or professional third-parties making money off the humble BMW e30 community--and mechanics who troubleshoot by replacing parts, not BMW specialists)! As my listings are free, I'd rather save my parts and resell next Fall (i.e. parts not yet listed: (i) BBS BMW e30 "Euroweaves", 15x7 et24 4x100 with hubcaps; (ii) Alpina A/C vent four-function digital readout (engine oil pressure and temperature, LSD differential temperature, and Manifold Pressure); and (iii) BMW e30 M-Technic deadpedal/footrest) to an e30 or BMW enthusiast/mechanic who truly appreciates them for what they are, and not focused as much on how much they cost and yet be completely clueless as to whether item is functional or not. 

As a result, if you feel you cannot leave feedback within a reasonable time period for the particular item--especially those whose "fitness is self-evident in itself" like a plastic body panel, requiring absolutlely nothing to test--please do not purchase this item, as I will block you from subsequent purchases. Similarly, many electrical parts, such as lights, horns, motors, etc, can be tested by using the applicable in-line fuse wired to a 12v car battery positive terminal, and separate wire connected to the negative.  Many switches can be tested the same way using a light bulb or test light. You don't need a BMW to do such tests, let alone a car. I stand behind my products, but not the clueless... 

Although I am ALWAYS willing to give POST-sale technical support, almost every product I sell on E-Bay is BMW Original Equipment, or Original Equipment Manufacturer, and should require little technical support with the vast amount of information from BMW Dealer's, Independent BMW Mechanics, on the Internet, local BMWCCA, tuning meets, friends, etc.  I will try to give you all the technical post-sale support you need, but please do some independent research BEFORE you contact me, and we will be better able to solve your issue.  Don't be like the clueless high-point E-Bay buyer who purchased a Motronic #173 ECU, complained about a "Check Engine" light (CEL), but did'nt realize that Motronic 1.3 has "adaptive learning" requiring repeated on-off cylces of the ECU to adapt from "brand new" factory engine fuel and ignition timing maps to be "re-mapped" for their specific used engine, which throws a CEL until adapted.   "Adaptive learning" and storage of fault-codes in ROM is the distinguishing feature between 1.1 and 1.3, and a little research by that NOOB would have gone a long way before accusing me of selling a so-called "defective product."  Of course that buyer is now "NOOB BLOCKED."             

Any buyer not leaving feedback will also be blocked. The Internet is also a huge forum that can democratically determine the validity of an item, and I would be happy to discuss the validity of any of my items, especially on any BMW forum. Of course that applies both ways, as in certain instances--especially small businesses--you may find it necessary to reply to my original threads discussing your "professional" expertise and competence, and please feel free to complain about me there also.

Finally, feedback for buyer's will now only be given after feedback is given to me the seller first.

If you have been blocked, do NOT attempt to contact me in any way, as I will first report you to E-Bay, then the applicable law enforcement agencies for statutory harrassment, and then the applicable Internet forum. YOU HAVE BEEN SPECIFICALLY BLOCKED BECAUSE I DO NOT WANT TO CONDUCT ANY FUTURE BUSINESS WITH YOU!

I pull weeds for a living, am rank-amatuer mechanic like most other's on E-Bay, and quite assuredly most buyer's easily have better skills and credentials, so the above requirements should be easily met. But as a rank-amatuer mechanic, I also currently use a fully-programable stock Motronic 1.3 ECU, which is comprised of: (i) Ostrich 2.0 EPROM chip emulator; (ii) connected via USB cable to a PC tablet running ETC Tuner-Pro freeware; and (iii) 27C256 EPROM chip burner to burn custom ECU chips once my tune is finalized. This is basically a cheap version of Miller's programable W.A.R. chip for Motronic ECU's, except a tuner can read, copy, and re-write any EPROM chip in hexa-decimel. However, I DO NOT SELL ANY ECU CHIPS OF ANY KIND, AS COPY-CAT ECU CHIP RE-BURNER'S ARE SCUM!  Also use MegaSquirt wired inside stock Motronic ECU box using stock m20 Motronic 1.3 engine wiring harness and sensors (except for wideband 02).  So yes, I am also familiar with independent standalone engine management systems.

This item will only be shipped to addresses where USPS "signature confirmation" is available (no P.O. boxes), or to United States servicemen/women having an APO, FPO, etc.

The Redline 75w-90 synthetic GL-5 gear oil with limited-slip modifiers will be drained-out for shipping.  AFTER RECEIPT, YOU WILL NEED TO INSTALL THE APPROPRIATE GEAR OIL BEFORE USE FOR THIS LSD TO FUNCTION PROPERLY!    

Please contact me if you have any questions.

Thank you for looking.  Please also see my other listings for tested and clean BMW parts at affordable prices.