Transmission id help

[Lonestar]

Hey all, got a few transmissions I could use some help getting id (I'll post pics when I can)
Got one standard nissan/datsun and one (maybe 2) auto datsun trans. I have to go dig out the 

auto but the manual has CA71B #1 stamped on it's bell housing, is this the right id number or 

do I need to look somewhere else?

 

[datzenmike]

Probably looks like this one I had from an '85 Z18ET S12 200sx. Mine had CA71B cast into the front case. It's the only 71B with a smooth front case rather than with ribs cast in.

 

 

All other 71B transmissions have this...

 

 

It's a 71B transmission, FS5W71B actually, which was used behind at least 5 different style Nissan engines including the L, Z, LD, SD and the CA series by using different bolt patterns on the front case to match the engine series used on. I looked but with over 1,000 transmission related pictures I couldn't find the one I took that also said CA71B. 

 

CA engines were used in the '84-'86.5 S12 200sx with the CA18ET or the CA20E engines. After '86.5 the transmission changed to the FS5W71C. As they only came with 5 speeds yours will also be a five speed. They came in two sets of internal gear ratios a wide and a mid ratio. The wide ratio was used on the '84, but '85 and '86 only the CA18ET (turbo) used the wide ratio and the CA20E used a mid ratio. You can easily determine wide or mid ratio by doing the following...

 

Place the transmission in first gear.

Mark the input and output clearly at 12 o'clock.

Have someone turn the input 20 turns while you count the output turns.

 

5.5 output turns you have a wide ratio 5 speed

6.0 turns you have a mid ratio 5 speed.

 

All Nissan automatics were 3N71B after April '71, replacing the Borg Warner 35s before it, and variants of this were used through '89. Again the bell housing bolt pattern determined what engine they fit. 

 

Front is the 3N71B. To the rear was a variant with 4th gear over drive added.

 

[mmerlinn]

On 12/28/2025 at 10:34 PM, datzenmike said:

 

Front is the 3N71B. To the rear was a variant with 4th gear over drive added.

 

 

The 4-speed variant is called L4N71B and various versions came in Nissan, Mazda, Dodge, and Mitsubishi vehicles. 2 different OD ratios (2 variants each) with multiple variations in rest of gear trains.

 

There is also another variant called E4N71B (Electronic valve body) found only in Nissan and Mazda.

 

https://mmerlinn.com/catalog/lizzy_c1995/jt_n71/jtn71010.htm#d

 

I currently have 21 cores in stock minus bells and tails plus bunches of loose parts.