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Step by Step - Installing an LSD into your open diff

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1. Remove diff (If you can't figure this one out, take your car to a shop and pay them to do the whole thing for you)

2. Remove cover

3. Mark left and right caps and also note top and bottom

4. Check backlash

5. Remove bearing caps

6. Remove carrier and ring gear

7. Keep left and right side carrier shims straight (I zip tied one side together, there were only 3 in my diff)

8. Remove ring gear bolts and ring gear from carrier.

9. Press new bearings onto new carrier

10. Loctite ring gear bolts and install ring gear onto LSD (this is where you would use the ring gear bolt spacers if you made them). Torque to 43-51 lb/ft for 10mm ring gear bolts, 65-72 lb/ft for 12mm ring gear bolts

11. Reinstall carrier into housing with shims.

12. Reinstall main caps on the correct side and rightside up. Torque spec is again 65-72 lb/ft

13. Verify that backlash didn't change

14. Reinstall cover

15. Reinstall diff

16. Add fluid

17. Accelerate out of corners like you never could in your Z before... :D


It's been my experience that the backlash doesn't change notably. It changed .0005" on my own diff, and I've never come across any posts from someone whose backlash needed to be readjusted after installing the LSD.


If the backlash did change more than .002 or so, then you just move the carrier to the left or right by adding shims on one side and taking away the same amount on the other side until the backlash is back to where you started. The shims could be ordered from Nissan, or you could take a trip to your local gear shop and see if they have anything close that would work.


Pattern won't change substantially because the pinion depth isn't changing. Setting pinion depth is hard to do. Everything else in a diff is pretty easy. This means that installing your LSD is easy.


Here is a link to a .pdf with a lot more info about other procedures involved in differential repairs. It shows pictures of measuring backlash, and has generic instructions for all of the gear installation procedures (pinion depth, pinion bearing preload, backlash, carrier bearing preload).


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I use SWEPCO 201 in my LSD, but before I found out about it I was running your typical auto parts store lube and an LSD additive. Additives are all the same, regardless of whether they're called "Friction Modifier" or "LSD Additive" or whether they say they're for Ford, GM, or Chrysler. VLSD's should require regular gear oil, but will require a different type of fluid inside the LSD, but that LSD works on an entirely different system and the VLSD fluid wouldn't be what you'd want to add to your CLSD gear oil.

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7. Keep left and right side carrier shims straight (I zip tied one side together, there were only 3 in my diff)


I'm assuming you had 3 shims on the left side and 3 on the right? Is that correct or 1 and 2? By chance did you measure the original shims? You mentioned the shims could be ordered through Nissan - is that a fact?




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It was actually only 3 shims. I think the right side had one thick one, and the left side had one thin and one thick. I was reading the FSM and they said that the shims were available. I haven't tried to order them, but they were at least at one point available. It's just a placeholder, so a closely sized shim from a GM or Ford should be fine too.

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This FAQ deals with installing a "regular" LSD into a longnose R200. There is some amount of crossover possible. For instance you can use the shortnose R200 KAAZ LSD in the longnose provided you get the diff that replaces the OPEN carrier and not the VLSD replacement.


The Q45 LSD's I'm not real sure about. There has been some confusion over how many splines the VLSD that comes in that diff have. I think some had 29 splines and others 30 splines. There were also some that had 13mm ring gear bolts instead of the usual 10 or 12 mm bolts. You'll have to do some research or maybe just open it up and see if everything swaps over.

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