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This is for anyone wanting to “repack” their H233B clutch-based limited-slip differential (LSD). It applies to C200 and H190A LSDs, too. It does not apply to other Nissan/Infiniti RWD/AWD diffs, such as the viscous LSD in R200V. It won’t cover the specific how-to’s of differential removal, setup, or installation, but will cover the basic assembly process. (I’ll answer any questions related to those topics, though.) All specific information (instructions, service data, torque specs, etc.) is in the “Propeller Shaft and Differential Carrier” (PD) chapter of the Factory Service Manual (FSM), and I’ll expect you to read it; there’s a section specifically for H233B LSDs. FSMs are available at https://www.nicoclub.com/nissan-service-manuals. Table of Contents LSD 101 Technical Objective Repacking Assembly Testing Some Q&A first... Do you have a LSD? With very few exceptions, LSDs were not standard equipment. You probably have one if: There’s an orange sticker with “LSD OIL” verbiage on the backside of the axle’s diff hump. Any of these test conditions are true (if there’s no distinguishable resistance, or if test #3 is false, then it’s an open diff): Transmission in neutral, one tire off the ground, spin the tire slowly; there’s resistance before the driveshaft rotates. Transmission in park/gear, both tires off the ground, spin one tire slowly; there’s resistance before the other tire spins in the opposite direction. Transmission in neutral, both tires off the ground, spin one tire slowly; the other tire spins in the same direction while the driveshaft rotates You’re cool enough to have the window sticker and it lists it. I shouldn’t have to mention to chock the front wheels and disengage the parking brake when testing, but there it is. What LSD configuration do you have? This boils down to “what truck do you have?”, since it’ll determine what configuration you have, what improvements can be made, and which parts/donors will help the most. What if you have an open diff but want LSD? You’ll need the entire LSD carrier from a truck with the same spline count. You don’t “need” the entire 3rd member, just the carrier, unless it’s got the gears you want. In most cases, the entire 3rd is easier to obtain. What donor trucks can you use? Pieces can come from any 2004 or older LSD, except Patrols. You should mainly limit this search to only WD21, D21, 00-02 Xterra, and 01-02 Frontiers. If you already have an LSD, the spline count on the donor is irrelevant. What’s your budget? Expect to pay $75-$500 for LSD carriers or complete 3rd members from local junkyards or eBay. If you want new OE pieces, some are still out there for $40-$50/ea (and you typically buy in pairs), but Nissan has discontinued the pieces. There are also other costs (fluids/oils, gaskets, seals, bearings, tools, etc.). Are you considering a gear swap? Make that decision since you’ll have the 3rd member down and apart. For R50 owners, you can get 01-02 Frontier or Xterra rear diffs with the same 4.363 and 4.636 gears and a desirable LSD configuration, but you’ll still need to find a 96-00 R50 to get the front gears if going to 4.636. All H233B 3rd members can be swapped to any other H233B axle housing, as long as the number of mounting studs and splines are the same. What’s your mechanical aptitude? Dropping the differential can be done with hand tools in an hour or so, provided no issues with hardware or rust. It’s a 70lb chunk of metal, so don’t drop it on your face. Rebuilding a diff can also be done with hand tools, but there are some specialty tools and knowledge required. Disregarding certain steps of the process can lead to noise and possibly failure. However, it’s highly unlikely you’ll find a shop willing to do this work, including 4wd and differential shops that do gears all day long. Don’t let those Jeep shops touch your truck; they’ll just fskc everything up, I promise. A Nissan dealerhip probably won’t do this work, either (at least not to the specificity discussed here). Consider this a DIY or HAFDIFY (have a friend do it for you) job. Is it difficult? On a scale of 1-10, I’ll put it around 7. It’s probably an all-day task for the average Joe/Jane, on par with changing out a timing belt or chain. The advantage is you can do much of the work on a bench, but the disadvantages are needing some specialty tools and the smell of gear oil. The job also involves bleeding the brakes, among other basic wrenching tasks. Is it worth it? If you off-road, yes. Even a weak LSD is better than an open diff any day. It’s not a locker (I don’t care what you or Nissan calls it—it’s not a locker), but it’ll act like one until it can’t. Although this guide is geared for off-road use, a moderate rebuild would do well on the street. It’s more affordable than a locker...however, requires as much work as installing one. So, if you’re on the bubble and the price of a locker is within reach, and you want max traction, consider getting an actual locker.

Testing Testing the LSD requires the means to apply torque to one side gear while holding the other stationary. I made these tools from some spare axle shafts (31- and 33- spline) and towing accessories. A digital torque adapter is used to measure breakaway torque. Splined ends cut off and welded to ball mounts and ¾” drive sockets: Undermount hitch receiver and backing plate: Digital torque adapter displaying a test result: With this setup, I realized my workbench has a 175 ft-lb breakaway torque before it wants to topple over. The advantage here, of course, is that I can mount this to my truck hitch (and I needed to once I started hitting higher numbers). Without such a tool (I doubt many people hoard spare axles and differentials like do), if you have the means to rig up a flange that mounts to the wheel hub and has a socket provision for a torque wrench in the center, you can actually test it that way, too...it's the same principle as the bench tool above. Otherwise the only other "test" is to do LSD-check test #1 in the Q&A section (first post) and feel out how much effort it takes to turn the tire. This will be entirely subjective. Barring any definition of the average mechanic, knowing that I could rip the truck if half if I wanted to: If it's relatively easy to rotate the tire, it's probably under 50 ft-lbs. If it takes a fairly significant amount of effort for you to rotate the tire, it's probably around 100 ft-lbs. If it requires just about everything you've got to turn it, it's probably over 150 ft-lbs, or you haven't put your purse down or eaten your Wheaties today. I also made a 3rd member mount because I need to set up a few carriers in the coming weeks: The joys of having a plasma table. Anyway, let’s talk about some real numbers. My torque adapter ranges up to 750 ft-lbs, and has a Peak-to-Peak setting that autosaves each peak readout. I’ve recently repacked 3 LSDs units using a bunch of new and unused FPs, some new FDs, some 1.6mm pieces, and the 3SS setup, all while testing incremental changes in between. For each test, I did 6 “pulls”, 3 in each direction. These were the general improvements observed: Using new/unused pieces: 10-15 ft-lbs per pair Series vs. parallel springs: 15-20 ft-lbs Using thicker (+0.1mm) piece: 20 ft-lbs per pair Triple parallel spring: 15-20 ft-lbs These are the following end results for those 3 LSDs and their recipients: @TowndawgR50: 4FD, 6FP (1x 1.6mm, 4x new), 3SS (1x SD, 1x SP, 1x SS) - Avg 236.5, Min 232.3, Max 240.1 @R50JR: 4FD (1x new), 6FP (4x new), 3SS (3x SS) - Avg 197.5, Min 184.4, Max 211.4 @RainGoat: 5FD (1x new), 6FP (1x 1.6mm, 4x new), 2SS - Avg 193.8, Min 178.9, Max 207.5 Notably, there were several other tests in between, but here’s how RainGoat’s LSD transitioned: Initial: 5FD, 6FP (4x new), 2SS: 151.1 ft-lbs With 1x 1.6mm FP: +19.4 With 1x new FD: +14.8 With both: +42.7 The aforementioned 95 WD21 unit I rebuilt using only the original pieces it came with averaged 142.8 ft-lbs. Not shabby given age and mileage.