RetiredZfool

I have a 260Z with a 4 speed 71B transmission and an R-180 differential. Looking for the plug sizes for both. I seached all the threads and found several mentions of plugs, but no one mentioned the sizes. I plan to order the more powerful Rare Earth Magnetic type. Recently I installed one in the oil pan. It was 16.4-1.33 from C.G. Enterprises (their code# is 1012SM). This is my first post and I'm still learning how to use the forum.

PredatorZ

Welcome to the Forums RetiredZFool, do you have a copy of the Sevice manual yet >? Heres a link to a free download. XenonS30 Did some research, so far No idea on tread size on those. What you might try is getting a stock one at local parts store, then measure it. Or pull yours and measure them. helpful tip, always remove fill plug 1st, that way if you cant remove it, you haven't drained it and cant refill. If you cant determine the size, take one to a Fastenal or similar vendor, they can determine your tread and size for you. It appears from 70 to 83 the plugs were all interchangeable. Ebay link http://www.ebay.com/itm/Datsun-Diffe...403#vi-content

RetiredZfool

PredatorZ, thanks for the reply. I have an orginal copy of the Service Manual in paper and also a downloaded issue, but they did not help.

I want to have the new plugs ready to go before I drain anything. I'm sure I will have to order the plugs and my Z would be down while I wait for them to arrive.

The local parts stores around here are not much help, but now that I think of it, there is a good shop in town which does a lot of Zcar work. I'll go by and ask them. Thanks again for the reply.

PredatorZ

From my reading it appears there are 2 drain plugs on the rear end.

PredatorZ

heres a part , fits trans and Diff, says it's 1/2 inch Mr. Gasket/1/2 in. NPT magnetic transmission and rear end drain plug (3680) | Oil Drain Plug | AutoZone.com

RetiredZfool

PredatorZ. Thanks. I'll go check it out, but the really strong magnets usually require ordering from a specialty company.

I checked the differential diagram and it does appear to show two drain plugs, but I can't confirm it. My Z is presently in a paint shop having the outside rear view mirrows painted to match the body color and remounted properly. Now I'll have to check if there are two drain plugs and decide if I want to replace them both. Changing the gear oil is not something I will do often and I don't expect a lot of fine metal debri (at least after this change).

Mobil 1 75W140 (a GL-5 product) is my planned gear oil to use in the differential. This is based on my average temperature, here in Georgia, and the FSM stated viscosity/temperature chart. I know there is a huge amount of discussion on oils and everyone seems to have an opinion about it. What type do you use?

I checked AutoZone for the plug and it has to be ordered. At least from the information I've seen, the transmission and differential drain plugs appear to be the same size. Also if a 1/2 in fits, it would take a 12.7 mm plug. I just have to figure out the length and TPI. Upon further checking, I found 12.7mm is not a commonly used size on any plugs. So I suspect the 1/2 in. at AutoZone is not truly 1/2 in.

Steve260Z74

You could also try Nissan. I have had good luck with parts going through Nissan Parts, NISMO and Nissan Accessories - Courtesyparts.com and NissanParts.cc - Your #1 Source for OEM Parts and Accessories.
The transmission drain plug is 32103-U8400.
The differential lists the same part number. Plus there is 38357-E4600, listed as PLUG-FILLER FINAL DR. I'm not sure if that's just a gasket.

You can the Nissan part numbers at CarPartsManual.com - Online Parts Catalogs for Classic Cars.

By the way, with living in Athens, you might be interested in The Mitty. It's at the end of this month. 2013 Speedfest at the Classic Motorsports Mitty Presented by Mazda: Classic Motorsports

RetiredZfool

Thanks Steve260z74,

I went to the local Zcar guru today and he said the Differential and Transmission drain plugs are 1/2" NPT. He seems to know all there is to know about Zcars (according to him anyway), so I will order one in that size and try it (I never fully trust anything until I have actually tried it). I've found many replacement plugs, but I've been looking for the size to order an especially strong Neodymium type. I found they aren't cheap, but if you're going to put in a magnet, it should be the strongest available. Dimple.com has one I will probably order.

So far, I have not gone to any organized meets or club gathering for Zcar owners, but I am interested. The Mitty would be a good start, but I'll be in Washington, D.C. then. My wife and I are retired and travel alot. Thanks for the reply.