Changing auto transmissions

[Don McNabb]

Can I change my 240z (1972) AT with a 4 speed AT from I think a Datsun Maximum. I was told the drive train is the same and that the two drive trains are the same except the 240 is a 3 speed and the Maximum is a 4 speed. Or is this a dumb idea

[Racer X]

1 hour ago, Don McNabb said:

Can I change my 240z (1972) AT with a 4 speed AT from I think a Datsun Maximum. I was told the drive train is the same and that the two drive trains are the same except the 240 is a 3 speed and the Maximum is a 4 speed. Or is this a dumb idea

Why not upgrade to a manual?

[Don McNabb]

I assume that is an easy option given the correct person does it. I was just thinking the RPM’ should be less if the Maximum trans is a 4 speed. Thanks for the response. 

[SteveJ]

Do you have the torque converter to go with the 4N71 transmission? Otherwise the OD gear won't work right. Also, there are two versions. L4N71B has a regular torque converter, and the E4N71B has an electronic torque converter. I'm not sure which one came on the Maxima, but the E4N71B version should have some wiring to make it work.

A little more searching suggests that if it's a Maxima transmission, it's the L4N71B.

Edited May 14, 2023 by SteveJ

[SteveJ]

Some info that may help you: http://datsun1200.com/modules/mediawiki/index.php?title=L4N71B_Swap