Hi,

Drop the differential last night and notice the part number on top which is: 38311 N3100

Been searching around to found out from which model it is and can't find nothing.

Help would be appreciated since I wan't to change a few seal and gasket.

Thanks as usual,

Joce

I believe that is the part number for the housing of an R200 but as to the model I am not sure as I think the same housing was used for the majority of R200s. Not sure if that helps maybe some of the more knowledge people here can help.

Cheers

JC

Thanks.

The housing is offset on the driver side. I guess this confirm it's a R200.

Next is the found out what the gear in it. I'll try counting turn tonight.

Is there a way to know if it's a LSD without opening the differentiel? It doesn't have a vent cover. Is this how you identify them?

The 38311 part of the number seems to indicate that it's an S130 differential according to my research materials but I can't find the N3100 coupled to it anywhere. Also the last five digits of the R180 limited slip differential part numbers end in 15, 16, or 20 so yours is not a limited slip. If it's offset to the drivers side, it's not an R200 but rather an R180.

Edited November 5, 200816 yr by sblake01

oh oh....... I'm getting mix up!

Check the following link

http://www.geocities.com/bry593/diffswap/diffswap.htm

Here is a copy of what that wesite is stating:

"At first glance, the assemblies look very similar. However, the R-200 on the right has a wider center, offset toward the driver’s side. To accommodate the offset, Datsun engineers designed the driver’s side halfshaft 3/8” to 7/16" shorter than the passenger side. For this reason, be careful not to mix these up and don’t use R-180 shafts on an R-200."

My scans are from the Nissan Competition Parts catalog. As you can see, the R200 is larger (as it would be). One must be careful when reading info on a site that's based on someone else's observation. To say that it's 'offset to the driver's side' would actually be true in both cases though more visable on the R180 at a glance. Which one does yours look like?

true

I'll post a picture tonight but it definetly look like the R200 in your picture.

I just go by the size and shape of the cover. Octagon-R200, smaller and semi rectangular-R180.

Perhaps posting a picture of the differential would help?

Edited November 6, 200816 yr by Zealous
Ok just saw the new posts, Moderator please delete this post

  Quote

To accommodate the offset, Datsun engineers designed the driver’s side halfshaft 3/8” to 7/16" shorter than the passenger side.

And, after measuring dozens of halfshafts from 280Zs, 260Zs, and 240Zs I have yet to find any variance in length. I've also had a couple Z racers measure the halfshafts in their piles and a couple parts hoarders measure halfshafts in their stashes. So far, no luck in finding a S30 halfshaft that is any shorter fully compressed then any other S30 halfshaft.

I was going to comment on that point also as I've read that somewhere before but I've never seen an S30 halfshaft that vaired in length from any other S30 halfshaft.

I have the same rear-end for my 240z.  I bought 1982 280zx 2+2 unmolested and that was the original rear end out of it.