S30 Transmission Differences

Manual Transmissions

Datsun/Nissan made several 4 and 5-speed manual transmissions available in the First generation Z car. Although there was a european 5-speed available for the 240Z, it is rarely seen in the US market. It wasn't until 1977 that a 5-speed was added to the Z car lineup in the US. The 1977-1978 5-speed is a "wide-ratio" transmission where the gearing is further apart , the 1981-1983 280ZX has a "close ratio" five speed transmission. Close ratio transmissons are preferred for road racing as they allow the driver to maintain a tighter rev range between gears compared to wide ratio versions.

Finding the "optimum" transmission for your car all depends on what you are wanting from your car. For most people the "best" transmission is what is already in your car. If you decide to upgrade your 240/260/280 4-speed to a 3.90 or higher rear end you should upgrade to a 5-speed for the additional gearing for highway cruising.

Gear ratio/Model Year 240Z 1970-1973 260Z 1974 280Z 1975-1876 280Z 1977-1978
1st 3.549 3.592 3.321 3.321
2nd 2.197 2.246 2.077 2.077
3rd 1.42 1.415 1.308 1.308
4th 1.00 1.00 1.00 1.00
5th N/A N/A N/A 0.864

Automatic Transmissions

In 1971 Datsun offered an Automatic transmission in the S30. The transmission Model was the 3 speed 3N71B. It is a fully automatic unit consisting primarily of a 3-element hydraulic torque converer, two planetary gear sets, two multiple-disk clutches, a multiple-disk brake, a band brake and a one way sprang clutch.

Changing of the gear ratios is fully automatic in relation to car speed and engine torque input. The car speed and engine manifold vacuum signals are constantly fed to the transmission to provide the proper gear ratio for maximum efficiency and performance at all throttle positions.

Below you will find Identification information and Specifications of the automatic unit.

260Z Automatic transmission ID plate location

How to read Automatic Transmission ID plate