I am doing some final restoration work on my 1970 240Z and have been considering swapping out the original 4-Speed Tranny for a 1973 240Z 4-Speed I have because I've heard that the 73' is a superior unit. I have 3 questions (1) what are the differences in the two units - is the 73' a superior tranny and why? and

(2), the 73' tranny is marked only with an "L4" and bellhouse # 7609776. It seems to have a shift stick mount about 2.5" to 3" further back than the original 70' tranny even though the overall length of the 2 trannys are identical.

(3) I've been told that the later model transmissions of the 240Z models just "bolt right up" but would like to have this verified and have a solution or answer for the discrepancy in the 2.5" to 3" rearward placement of the shift stick. Thanks for any help.

1.) The later transmission is said to be a slightly stronger unit. But I doubt that the strength difference (if any) is significant for street use. The ratios are similar.

2.) Yes, all of the Zs from '72 on had the different shift linkage.

3.) Other than the linkage issue, the later transmissions are a straight bolt-in swap. But the linkage difference will require you to either enlarge the holes in the tunnel and console, or have the later style shift lever custom modified.

All this being the case, I can't see that there's enough benefit to using a later 4 speed transmission in your early car. If you were going to make the mods for a 5 speed, maybe. But not for just a later - but very similar - 4 speed.

Arne,

Thanks for the information. Can an early model 240Z shifter be modified? Do you know where I can obtain an existing modified shifter? There happens to be 5 shift levers on eBay right now for about $20 (see item # 300267695928).

I'm tracking down a 5-speed. Will the required modified shifter for the 73' tranny and the 5-speed be the same?

For either the 73' or 5-speed will the tunnel opening have to be cut and by how much (to the rear or front)?

Sorry to throw back so many questions but any help would be appreciated. Thanks.

Robin

IMO if your going to make the swap, wait til you have a 5 speed. Unless your current 4 speed is shot, as Arne mentioned, you won't see enough of a difference to make it worthwhile.

The cutting of the tunnel required is minimal, about an inch or so, if I recall correctly, and to the front. You don't even have to remove the metal, just bend it back out of the way. That way, if, in a future life, you want to do a completely anal-retentive restoration, you can just fold it back and weld it up. It'll be our little secret, .

cheers,

p

The early shift lever will not work at all with the later type transmissions. You need a later lever. The same later lever would work for any '72-up transmission (except the T5 from a late ZX Turbo). The lever modification includes cutting, welding and bending.

Have decided to stay with the original tranny. Seems like the right thing to do at this time. Hope to have the engine back in this week and really want to try to get a drive in B4 the snow.

Appreciate your comments and advice. Thanks to you both.

Robin

I know it's an old topic, but I hope it's ok that I use it for my question

I have a 10/70 manual 4-speed US-spec 240z. I've purchased a 280Z 5-speed transmission that I want to use. I'm not going to change the diff at this time.

Is it a direct swap or do I need any other parts, like a 5-speed transmission mount/crossmember or a different driveshaft? I've searched but didn't find an answer (I'm probably just bad at searching :stupid:).

Just have to be sure before the project becouse it isn't that easy to find parts here in Europe.

Edited May 3, 201014 yr by Kimi

I recently put a 5 speed in my 4/71 Z and everything fit nicely with nothing extra to buy except for replacing "wear" items like clutch, T/O bearing, rear engine seal as part of the job. Transmission tunnel hole needs to be enlarged and a late style rubber inner boot used. The later boot is held in place with a trim ring and fasteners rather than just being a press fit in the opening like the early boot.

Dennis

Thank you Dennis for the help

This might help. found some useful info.

http://zhome.com/ZCMnL/tech/AandBtranny.htm