Differential Help... 38311 P9000

[z boy mn]

Hey everyone, when I bought my 240Z it came with a damaged R200 LSD 4.11. I'm running on a spare 3.90 now, but I recently decided to repair the 4.11.

This has turned into a major headache as I can't seem to find parts diagram for the 4.11, much less the parts. It looks like it was recently overhauled, too. The gears look new, the cluch packs look pretty good, but the bearings are shot and there are some missing washers on the pinion gears (I think this is what they're called...they're 4 gears that transfer the torque to the axles). So...no wonder it rattled and clunked and made very bad noises.

Does anyone know about this rear end? The case says, "38311 P9000". The closest I could get to that at Nissan was "38300" which looks close, but the 38311 has an extra center bearing, so I know it's not exactly the same.

The original owner said it came out of a 240SX Turbo, but without the car Nissan can't find the parts (some had 4-wheel steering, some didn't, and not all the diffs were the same). We found some likely close cousins, but the parts are expensive and I'd hate to spent $800 putting this back together only to find out the parts aren't compatible.

Or...can I take the 4.11 gears out of this and put it in my spare and rebuild that one instead? I'd lose the LSD, but maybe I could put in one of those helioc ones I saw on ebay for about $400. (see below)

http://www.ebay.com/itm/OBX-LSD-Limited-Slip-Differential-Nissan-300ZX-240Z-240SX-R200-End-Z31-/121131648924?pt=Motors_Car_Truck_Parts_Accessories&hash=item1c3402479c&vxp=mtr

I do know that this particular swap was pretty popular...and the original owner had good reason to think this would all work....but I'm stuck. Any help would be appreciated!

Edited July 17, 2013 by z boy mn

[John Coffey]

The car would be a 200SX Turbo probably 1985 or 1986.

[Carl Beck]

I know next to nothing about differentials - but looking at the OBX on EBay - it makes me wonder why they sell for $400.00 then the Quaif and Torsen/Gleason units were in the $1600.00 to $2500.00 range..

Are these OBX units Chinese knock-off? or what?

FWIW,

Carl B.

[cbuczesk]

The OBX is a Chinese knock-off. The problem with them seem to be with the bolts and washers. There's a lot of info on Hybrid Z about it. Upgrade the bolts and washers and you're good to go. I have one in my 280Z ITS race car and it works fine.

Chuck

[Patcon]

The bearings should all have numbers on them. Get a magnifying glass or some reading glasses and try to find the numbers on the bearings. Google them or talk to a bearing distributor to find a match many bearing houses can help with seals too, the washers I don't know...

Charles

[z boy mn]

Thanks everyone for your help. I spent much of last night trying to determine how many different thrust pinion washers Nissan made for the 240SX and 300ZX...thinking that if I order a set of each one, one of them will have to fit. So, turns out there are 5 different part numbers and I figured I'd order all of them and send the ones that don't fit back. Not sure really how to tell if they "fit" or not...is there a clearance that's standard? Also, one issue is that all the diagrams show a viscous LSD, not a clutch-based LSD...I'd hope the washers were the same.

Of course, this is assuming that there are supposed to be washers there...maybe they're not missing at all. Still, seems like the gears really flop around on the pinion (not sure if this is the real word...it's the thing the four gears are connected to inside the LSD).

Also, if I can't find a washer to use, I'll try the OBX option. I'm not a drive train mechanic, but it sounds like if I take it to one who can check it out, it might be a good option. I'll also check out hybrid Z and start reading there. If anyone has any other suggestions, I'm all ears!

[Zed Head]

I think that you missed the point that John Coffey was making in Post #2. 240SX's didn't come with turbos or CLSD's. But 85 or 86 200SX's might have. Look for 85/86 200SX Turbo parts.

[John Coffey]

Also, make sure you're comparing parts within the long nose R200 and the short nose R200 models. There are differences.

[z boy mn]

Got it, and thanks for your help. Sorry to be so thick when it comes to differentials and these parts...I've obviously got a lot of learning to do. I'll do some searches and try and make sure I'm looking at the right kind of LSD.

[RichardDG]

Sorry for late contribution to Thread, but just found it in Internet search

38211 P9000 is the Part Number of an R200 Diff case only. 38300 plus 5 digit number/letter suffix is the Part number of a Diff ASSEMBLY (complete - ready to bolt in). The one same numbered case can hold any ratio from the range available - those different Ring and pinion sets fit and are interchangeable. The diff centre is interchangeable between open and closed/LSD. But the one sme numbered case accepts only same size and number of bearings.

Best bet to overhaul is matching

[z boy mn]

Richard, you're not late, you're right on time! I had to push the diff back for other projects in the summer, but now I'm back on track and just started hunting down a bearing set for the soon-to-be overhauled 4.11 LSD. Wahooo!

[jl240z]

I am looking at the OBX option as well.  Rich Bryant,( rich_bryant_is@yahoo.com), sells the upgrade kit for $34.  The unit had a lot of bad press and failures early on but the kit seems to fix it.  He has a web page that describes how to do it step by step. The price for the diff on ebay is $415-$479.  It sounds to good to be true but it may be worth a shot with the kit.  I have a R200 LSD clutch type as well, but it has a 4.67 in it.  I bought a 3.91 open diff so I could put the LSD into it.  I found a company in Japan, Negun Co. LTD, that sells part for it so i can replace all the clutch disc parts, but i cant get on the site.  Something about computer problems, theirs  or mine and i get kicked off it before i can inquire.   I did see one page that said the clutch disc set for one side was $27.  They had other kits that may have included bearings and seals, but i couldn't get on the site.  I think i hat ill write them and see if they will email me back so i can do it that way.  Anyway in case you didn't already know i am passing it on,  I may just order one of the diffs and a kit and see what happens.  Good luck