Ok guys, now it may get a bit techy in this post 🙂 I collected A LOT of information about transmissions over the past months and i’d like to put them all together into one single post. A lot of information is floating around the internet but it’s tricky to puzzle it all together, keep the overview and sort out the wrong information.
This post is focusing on the 1970-1974 240Z and will not include a lot of information about later transmissions nor any Information about the Transmissions in the L20 / S20 equipped JDM only models (thus JDM L24 model is included).
Trust me, it’s complicated enough.
And just sayin – some Data may be incorrect but i tried my best to get it right 🙂
1. Transmission type code key / identification
Before we start, first a Key to understand the transmission type code.
I already listed this in the past, but decided to make a better graphic for easy overview.
Note that this chart is only about Manual transmissions:
2. Factory transmissions:
Depending on the country and year, there were different Factory Transmission options. But there are two main groups used in the 240Z:
Early “A-type” (1970 to late 1971, varying a bit depending on country and Type)
Later “B-Type” (1972 to 1974, Also used in later Generation Z’s and other cars)
The “Type-Letter” is refering to the last Letter in the transmission model code.
Early type for example is FS5C71A, later type FS5C71B, and so on, see code chart below.
Within each of these two main Groups, there are similar three subgroups:
Nissan 4-Speed Manual, Nissan 5-speed Manual and JATCO 3-speed Auto.
I made an overview Including the Type-code for easier understanding (click for full size):
2.2. Transmissions according to Markets:
Which transmission was available in your cars market? Well – you can find this information in your FSM (Service Manual) but here’s an overview:
USA & Canada (LHD): 4-speed Manual and 3-speed Auto*
Europe (LHD): 5-Speed Manual
UK (Europe RHD): 5-Speed Manual
Australia (RHD): 5-Speed Manual, 3-speed Auto
Japan (RHD): 5-Speed Manual, 3-speed Auto
*Optional and competition transmissions are not included in this chart
Here is an Example of the 1972-1974 Service manual listing all B-type transmissions according to the dedicated market-model (first row).
For earlier model years, just replace all “B” with “A” in the transmission type code 🙂
3. Optional transmissions and Gearing
In Europe and Japan there were optional competition and racing Gearsets and complete gearboxes available for the Z’s. Here for E.g. JDM “Nissan Sports options”:
In USA however it was a bit different since they never got the 5-speed Manual Box:
– They offered Retrofit-Kits to install the Roadster 2000 (SR311) FS5C71A Transmission to the 240Z
– From 1977-1983 the 280Z FS5C71B Gearbox got available with optional competition Gearsets (and probably as a complete gearbox) which was also used as competition or racing part in the 240Z’s (with optional shifter-kit if used in an 1970-1971 car!)
– Anyhow a few sources mention that at least at some point the Euro / JDM A- and B-Box was also sold officially as an optional part.
Here’s a Pic of the 1978 USA Datsun 240Z Sports Option catalogue for example:
See complete list of Factory and optional transmissions / gearsets below.
4. Differences between A-, A- and B-type(s)
First a bit of history. The early 5-Speed “A-Type” Transmission was not developed for the 240Z, but carried over from the Datsun roadster 2000 (SLR311) and probably also used in other older Datsun models.
To fit the L-series motor and the 240Z Specs, the 240Z-Transmission was fitted with a different clutch bell housing, longer mainshaft, tail Extension casing and one of the shift rods is different too.
That’s why the Roadster Gearbox is often refered to as “short tail” and the Z-Gearbox as “Long tail” Fs5C71A Transmission.
The US market got 4-speed non-overdrive gearing, but im not sure if there was an A-type 4-speed maybe used previously in other datsun’s as well..
Here’s a picture of a FS5C71A “short tail” from a Datsun Roadster (From the Roadster FSM)
While here is a view of the FS5C71A “Long tail” from the Datsun 240Z (Picture from the Nissan Motorsports schematic Catalogue). Also see the first Pic at the top of this post, which is the FS5C71A Factory European Spec 5-speed that came with my two early 1972 240Z’s.
Then there is the B-Type from the 1972+ 240Z which is a complete redesign of the “A-type” transmissions.
– The biggest difference is the two-piece Bellhousing of the A, while later B-type has a single piece bellhousing.
– Another visual difference are the Cast-fins on the outside of the housings as seen in the pictures above and here:
Here is a comparison between the A- and B-type from the S30 from the japanese G-works Fairlady Z S30 Magazine vol. 2:
– The A-type got the infamous so-called “Monkey Motion” rubber mounted shifter-stick while the B-type shifters have a solid cross pin. Later Model C-types are retained in a top cover plate by a circlip (Called “Top Loader” in american trannies):
– The gear ratios were different on both A- and B-types (both in 4- and 5-speeds)
– Due to the redesign the Shifter stick position is moved stlightly to the front in the “B-type” (See below).
– There were also other changes so be careful when swapping transmissions!
– Note that the B-type Transmission was used over a Long time and in several cars after the 240Z, so it got various design-changes in later models which will or will not fit the 240Z 1:1.
Here’s a Comparison between the 240Z transmissions, Left to right:
FS5C71A “Long tail” 5speed from the 1970-1971 240Z (non-US)
FS5C71B 5speed from the 1972+ 240Z (non-US)
FS5W71C from Later Datsun / Nissan model cars
3N71B Spline Type 3-speed Automatic (1972+ non-Euro 240Z)
4.1. Transmission interchangeability
4.1.1 Datsun Roadster 2000 FS5C71A into 240Z:
In America People used to install the Roadster 2000 FS5C71A transmission to get a 5-speed into their Z. This Retrofit was officially sold by Nissan / NISMO USA.
I was able to find a receipt of someone who bought this swap at a nissan dealer including all the part numbers needed:
4.4.2 A-type with A-type
Swapping an Manual A-type 4-speed to a 5-speed should be a simple thing without any modifications needed since both have similar length and shifter positions.
4.4.3 A-type to B-type
Here you can see a A-type US-spec 4-speed Transmission (front) and a B-type US-spec 4- or 5-speed in the rear. According to the source, both transmissions are within a small fraction of an Inch of each other in total length. The 510 Transmission identification Manual (See Documents below), Says that all 4- and 5-speed both A- and B-types of the 240Z have a total length of 31.5In / 775mm, so this might just be within the tolerances.
You can see the Centerline of the “A”-Shifter in the foreground (line #3) sits about 2.25 inchehs behind the Center line of the B-type Transmission (rear, line #1).
Line #2 is the rear end of both transmissions.
To install a Later B-type five Speed, which was sold as Competition Part in US at one Point in a car that was initially equipped with an A-type (four Speed) Transmission, Nissan sold the “Shifter Kit” (Part number 99996-E3030) as seen on the B-type Transmission in the back. It’s basically a bent stick where the original one is straight. The Shifter kit is not available anymore (Courtesy Nissan Information to my request in 2016) but i guess you can just bend the original stick. Also a different propeller shaft is needed.
The shifter sticks are not interchangeable between A and B-type and 4- and 5-speeds.
188.8.131.52 Center Consoles A- and B-Type?
There are two different types of Center consoles. One with the Ashtray in front of the stick (1970-1971) and one behind (1972 and later). Some sources say that’s because of the difference in shifter stick Position in A- and B-transmissions (See above). I Made a picture for comparison:
I cannot confirm above information, since both of my cars came with the Early A-type 5-speed and the later Center console with the ashtray behind the stick (See picture below). This would be a wrong combination according to the sources but i’m pretty sure this was the factory equipment in both of my cars:
4.4.4 Later Datsun / Nissan transmission swaps:
There are possibilities to swap to a huge array of different Datsun / Nissan Transmissions, but to not make it more complicated for the Moment, i will make a separate post about this Topic later.
5. Transmission / gearing overview:
I made an overview based on existing overviews and doublechecked everything with FSM’s, schematics, competition catalogues, E-Fast database, Original Micro-fiches and so on for hours. however sometimes some data was not 100% clear. anyhow i think this is the most complete overview about 240z Transmissions and (later) Options.
Note that this list is not 100% complete since there were also optional single gears to choose and 4-speed optional gears which i didn’t include in the list.
Also note that the part number for the same part may be different in different markets or may have changed over the time.
Click here to download the full PDF file (Free)
If text is coloured in a certain colour this means the “source” with the same text-colour mentioned this data, while all the other sources mentioned the black text. Sometimes it’s obviously a typographic Error but in some cases im not sure.
Also note that there are several other Datsun / Nissan 71A/B Transmissions and Gear kits wich will fit the original transmission and / or L-Series motor but not listed above since they were used in different cars. The list above only contains transmissinos wich were used by factory or sold as option through nissan for the 240Z / Fairlady S30 in different markets.
6. Brass “Warner” vs Servo “Porsche” style steel Synchros.
There are both Porsche style steel servo synchros and Warner style Brass synchros. What’s the difference? I have no own experiences but i found following information online:
– The porsche type reacts slower than the warner type
– Porsche type shifts smoother than Warner type
– Porsche type snycros dislike being “speed shifted” (probably due to lower reaction times)
– Warner type is great for drag racing (Fast shifting possible due to fast reaction times)
Since all “competition” transmissions came with porsche synchros despite having slower reaction times, i guess they can handle slightly more power and / or last longer under heavy usage compared to brass synchros. Otherwise it would not make a lot of sense to have these in “competition” (or non-US standard) gearboxes.
Spareparts – especially for the early manual 5-speed are hard to find these dase, but below you find some adresses that still sell some parts:
8. Transmission Service Manuals and useful Links
“Five and dime” 510 Magazine Volume 11, Issue 4, Datsun / Nissan Transmission identification guide (See Pages 04-09 Tons of informations!)
– Five and Dime vol11 issue 04 (Nissan Transmission Identification)
Datsun FS5C71A transmission service manual (From Roadster 2000 SR311 Manual, will also work for 240Z 5-speed except a few design changes):
– FS5C71A transmission service manual (Roadster 2000)
FS5C71A / F5C71B Parts exploded view / Partslist:
– NissanMotorsportsSchematicCatalog (99996-M8015)
Datsun / Jatco 3N71A Automatic transmission Manual:
– Datsun – Service Manual – Full Automatic Transmission – 3N71A
An overview about different nissan / Datsun transmissions and gearing:
9. Thanks for reading
I thank anyone who provided some information for this Post.
If you find any mistakes and can prove it with an official document, please let me know so i can update this post with the correct Information!