Problem with NISMO clutch lsd installed in s13

[zmannz]

So, I bought a supposedly unused or lightly used nismo clutch type lsd a few months back. I was told it was the correct diff for an open housing and that it should bolt right in. It already had the bearings pressed on it and they did not look used. The exterior of the diff looked brand new. I was not told the model but it was supposed to have been switched from 1.5 to 2 way locking. From the way the locks looked to be sitting I would say it had been.

I finally installed in the open diff housing of my 92 s13 coupe this weekend to drift on sunday. I removed the old one and installed this one in just a few minutes on my shop table. I disassembled it and kept all the left and right pieces together. I definitely pulled the bearing caps and the spacers and put everything back for those the way it should be and torqued it all down correctly with new nissan oem bolts for the caps. I pulled the ring gear from the open diff and used new bolts to install it on the nismo. After reassembly I checked the lash with a mag base dial indicator and it was perfect. I snapped the output shafts back in and I did notice that while the left one cleanly snapped tightly in and had little to no slack, the right one seemed to be easy to rattle in and out a millimeter or two and I could easily unsnap it again wheras the stock diff held them in like the left one. There were wire snap rings in the output shaft holes of both diffs.

Anyway, so I closed up the diff and filled it while on the vise with 80w90 dino with friction modifier for breakin and let it sit over night. The next morning I threw it back in and bolted it all back up. No leaks, felt good until I noticed I could turn the driveshaft a little with the wrench I was using to tighten the connecting bolts even with the e brake on. No clutch diff I have had ever did this. After I put it on the ground I started the car up and put it in first to move it and I let the clutch out and only got a grinding noise, the driveshaft turned and made a little noise in the diff but the car makes no effort to move. I then turned it off, left it in gear and left the e brake on, and I could roll it like it was in neutral.

Any ideas on what could be wrong with this thing? I have had a kaaze diff I installed in another car but it was not adjustable lock type and it didn't have the break tension feature this one does. I have not attempted to change the breakaway setting in the right output shaft area yet. I was told I could f*** it up if I turned that too far. I am tempted to try that but I wondered if anyone had heard of this before. I have good contact with the previous owner and he got me the info on the guy he got it from becuase he had never instaled it. I am waiting/hoping to hear anything from the original guy about what it could be. I paid 600 for this thing, and at this point I am praying I was not sold a trashed diff.

[compactfean]

It sound like the.output shafts you have in there aren't the right spline count for the lsd. I did this once with hubs (got the.twin turbo hubs) and made that grinding sound because the axles were.significantly smaller and just spinning inside the hub.

[zmannz]

Hmmm, I will definitely check that. Would I not have had a bad leak out of the output shaft seal area if that were the case? (seems the whole shaft diameter would be smaller if the tooth count was lower) I filled the diff while it was on the bench and it was on its side and rotated around a lot during installation. I will be sure to mic the output shaft and check the tooth count, I have half shafts from nearly all years of s chassis about and at least one z32 unit in the parts bin. Any other ideas? I have had a 1 way diff in a z31 failed and I still had a peg leg as long as I was light on the gas. I am starting to think after looking at the parts diagram for it that I have no tension on the part that controls the breakaway in the right side. I also had the loose output on that side so I am wondering something in that section is broken. Well, at least I get to do something new tonight. I have never been into a 1.5 or 2 way diff yet. Maybe I will get to weld and machine something woot!

[compactfean]

The section that seals the output shaft is the same on all r200 diffs. the shaft with the splines is cartridge specific. For example, I just got done doing a stock 240/q45 hybrid and the ” larger” output shafts fit and seal perfect with the stock seals. I'm betting the nismo needs 29 spline outputs from a vlsd. I think the stock outputs are 27 spline and break very easy.

[zmannz]

Well, the splines are matching up correctly in the output shaft holes. I took it out last night and checked everything out. The lockup between the wheels is working perfectly. The problem is that the input shaft from the drive shaft is just about spinning free intead of actually making the wheels turn. I did confirm that the backlash clearance is within spec, as well as the side play. Something in the diff that mates the movement of the ring gear to transfer to the output shafts is just spinning. I am guessing its worn out clutches at this point. I will disassemble it tomorrow and see whats up.

[compactfean]

If you had worn clutches it would behave like a open diff. Not, not do anything at all.

[OutToWinPAHC]

Sounds like a runout backlash issue to me

[zmannz]

The lash and side play is good. The last two owners did not install it but the earlier of the two did disassemble it. I am going to break it down tonight and see what exactly is wrong. Finally found out the exact model and got a diagram of how it should look.

[zmannz]

Alright so compactfean was right the ouput shafts are different my b.

[zmannz]

Anybody know which stub axles I would use for this diff? I have 6 bolt halfshafts that came with the open diff (oem on the car) I thought I had z32's in my junk pile but I do not. From what I can tell the stubs I have now are 29 spline and I think the diff needs 29 too, the od of the splined part is just bigger.

[zmannz]

Alright so based on this:http://www.driftworks.com/forum/technic ... blems.html

I think the next size up in the line of stub shafts would be the s14a's. I think I am going to email nismo about it and see if they can help.

[compactfean]

Im having trouble understanding you're terminology. So if the output shafts you need are vlsd output shafts, than will need jdm 6 bolt vlsd output shafts (to match your stock axles) or j30 or 300zx output shafts with j30 axles.

[zmannz]

The stub shaft is the most inner part of the halfshaft with the splined part that has the 5- or 6-bolt pattern on the opposite side. I counted the splines in the diff again last night, it has 30. I am thinking j30 halfshafts will be my cheapest way out. Well, at least I know what I need. I am actually about to transfer most of my new coupe I was going to put this on into my old car and built a strictly track only car so it will be while before i need anything.