Transmission Identification

[Byron510]

Mike,

You seem to have a pile of info on these transmissions and seem to be the guy to ask. So I thought I'd pose the question in this thread:
Do you have a list of the various long tail 5 spd's (Z,ZX, PU) from 75-83?
I have 4 transmissions in my stash, but I want to find the late ZX box, with the .75 OD (I believe this is the tall one, right?). Is there anything specific I should look for? A specific PN located ???

Thanks Mike,
Byron

[Byron510]

Well, I really need some help identifying these transmissions.
I thought they all were 280ZX, but closer inspection when I laid them down made it obvious that the center transmission was a napZ installation, and when I dusted off the casing I had wrote 83 200SX – 1999 – stating the car and the date I took it out.
So this leaves the other two; I had written .72:1 on the trans on the left (when viewed from the tail shaft end on the last few photos). I don’t know if this is right, or how I know this at the time.
What I’m really looking for here is the tall overdrive 5th late 280ZX transmission. Can any of you transmission guru’s identify this by the case? I looked all over these things for numbers. I know Mike has posted many alpha-numeric numbers, but all I found was what appeared to be a serial number on the bell housing – and I don’t know if this does any good.

Any help would be appreciated, I’d hate to have to crack these open and count gears, but if that’s what I need to do…













Any light you can shed will be more that I can identify from these external shots.
Thanks, Byron

[datzenmike]

I'm sorry Byron, somehow I missed seeing this post on Sat. and it 'fell off the page'.

Well they were all made no earlier than '80. Crap I'm at work and can't seem to link to pictures... I'll have to finish it at home later.


BTW..... I can narrow it down to two. One of these is from a Z series engine if that helps.

[Byron510]

Yep, the one in the middle is a Z series trans. When I laid them down and looked at them from the rear, the bell housing bolt pattern offset was obvious.

With the other two, one has a switch (reverse, maybe?) up by the shifter linkage. The other has the boss, but it's not tapper out. Also the oil fill plugs are on opposite sides...
The tans on the left was the one I'd written .72:1 - buy I'll be honest, I don't know how I knew this at the time as I know I did not take it apart. I can only assume that I knew its origin.
The last time I used this transmission was in the EFI wagon the Merlin now has.

Byron

[datzenmike]

Yep, the one in the middle is a Z series trans. When I laid them down and looked at them from the rear, the bell housing bolt pattern offset was obvious.

The far one is a Z series tranny.


The far left is the Z series.



The close one is the Z series.

With the other two, one has a switch (reverse, maybe?) up by the shifter linkage. The other has the boss, but it's not tapper out. Also the oil fill plugs are on opposite sides...
The tans on the left was the one I'd written .72:1 - buy I'll be honest, I don't know how I knew this at the time as I know I did not take it apart. I can only assume that I knew its origin.
The last time I used this transmission was in the EFI wagon the Merlin now has.
Byron

The numbers on the top bell housing don't mention the year but it does list the month made. No help there. (the 3N71B auto does list the year and month of manufacture) But I digress.....

Once the tranny is out, if it isn't marked, the year and model it was in is lost. There is nothing on it that definitively IDs it. Some times it can be narrowed down by the shifter, rear mount, speedo pinion, front counter bearing size, neutral/top gear switches and identified by what it ISN'T.

The Z series tranny (going by the switches) is not from the S110 and has to be for a 2wd 720 truck before '83. Can't be from a 4X4. BTW, the switch on the tail stock is the neutral switch, the reverse light switch is close to the bell about half way up the right side.

The other two were made no earlier than '79-'80 and judging by the shifter they are not from the late 620 truck. This makes them consistent with the ZX tranny and unfortunately also the '81 and on Maxima which is built on the ZX platform and shares suspension and drive line parts.


Byron to test the OD 5th. simply place in 5th and mark and turn the input 10 full turns. Mark the output spline and count the turns. A 0.773 ratio will turn close to 7 3/4 turns. A 0.745 will turn about 7 1/2 turns. This is way easier than taking the tail stock off.

The next closest ratio is just over 8 turns but most are higher.

Hope this helps.

mike

[merlin]

I have the 5 speed and L20b out of a early 1980 720 any ideas what ratio that is??

[datzenmike]

3.321
2.071
1.308
1.000
0.883

Unless it's a 4X4 then :

3.592
2.246
1.415
1.000
0.813 (a 4X4 won't have a speedo pinion in it)

[Byron510]

Thanks Mike,

I brought one home on Sunday, I'll unwrap it when I get home on Friday (up in Fort St John right now), and I'll let you know what I have. Thanks for our help.

Byron

[merlin]

3.321
2.071
1.308
1.000
0.883

Unless it's a 4X4 then :

3.592
2.246
1.415
1.000
0.813 (a 4X4 won't have a speedo pinion in it)

nope, it was a 2wd... pulled it myself.

[datzenmike]

It's almost identical to the '77-'78 620 and the '77-'79 280z trans.

[Rheis]

I have the one with the taller 5th in my garage... I could go look for some numbers for you if you would like

[Byron510]

I have the one with the taller 5th in my garage... I could go look for some numbers for you if you would like

I was about to send one out to get an overhaul. Do you have a good transmission Rheis? If so, consider it sold.
Byron

[Rheis]

No unfortunately this transmission is no good. Its the one I pulled from my car last year because was staring to make a lot of noise. This transmission was great for the highway and I prefer it over the other zx that is in my car now ... if you would like I can grab numbers and pictures so you can match one of those trans to it

[Byron510]

Thanks Rheis,

I'll also figure out the ratio on my own boxes when I get home. I'm looking for the tallest OD 5th out here as I'm running either a 4:44 or 4:375 rear gear depending on weather I'm using the R190 or R180 - I'll need that 5th for the Canby drive, and any drive for that matter with short 13" tires and a low rear gear.
Post your 5th gear count as Mike suggested above, I'll do the same for my box.
Byron

[69dime]

OK, so what's this one? It looks similar to the Z-series, but not exactly. The crossmember was moved back in the 510 I pulled it from, and it has a shortened driveline.