My restored, stock 71 240z has a perfectly good automatic transmission. My plan is to find a manual transmission soon, and hang on to it. Someday, if or when the auto trans goes, or I get sick of it, I will have the manual ready to go. And yes, I will also need ALL of the other bits and pieces to make the conversion. My issue is, should I go with a 5 speed or the original 4 speed. It seems putting a 5 speed in requires some modifications. I don't have a preference to either 4 or 5 speed, but I think putting in the 4 speed would be easier. I really don't like the idea of whatever changes or mods the 5 speed might require. I would just like to hear some opinions on this subject. Thanks.

I'd say if you can go with the 5spd, it makes interstate driving much more pleasurable. The only modification i know of is that if your car is still a series 1 than your shift lever position is different and you would need to switch to the series 2 center console. Other than that the 4spd and 5spd transmissions are interchangeable. Not sure about the drive shaft length thou.

I have a 4 speed with a 3:54 diff that I may be deciding to sell - not sure yet...........the 3.54 has plenty of get up and go due to the gearing ratio. I installed a 5 speed with a 3:9 diff last year and have the other set in storage. My 4 speed is dead on and the diff was perfect............pm me an offer if you are interested. Still thinking if I want to sell them or keep them.

Hey there Glassguy.

Your auto most likely has a 3.54 diff, which coupled to a five speed, makes a good combo in my opinion, and a good touring car.

Mine is turning 3000 at 60 MPH, so i seldom use 5th cog. I might drop it into 5th at around 70 MPH, but seldom reach there.

Olzed is right......your auto Z has a 3.54 diff. A 4 speed will be turning 3,000 rpm at 60 mph with that diff......not fun on a long trip. If you have a late 71 Z with the long driveshaft, there's no difference between installing the 5 speed versus the 4 speed.....both transmissions are exactly the same dimensions.The 5 speed will work much better with the 3.54 diff. If you have an early 71, it could require some mods. If you have a late 71, the 5 speed is a better mousetrap IMO.

The mod to worry about is the opening in the tunnel for the shift linkage. The early Type A transmissions will fit a '70-71 w/o mod, but for the most part here in the USA that means a 4 speed, as Type A 5 speeds are rare around here.

The later Type B transmissions will require the opening in the tunnel to be enlarged, or to have a custom shift lever fabricated. Type B was available in both 4 and 5 speeds here in the US.

Chances are that most any used transmission you will come across will be a Type B. The Type A 4 speed was only used in '70-71 cars.

In general, other than the shift lever issue, there are no other differences between swapping any of these transmissions into your car. All the other requirements will be the same.

For what it's worth I have 2 - 4speed transmissions with the matching differentials from the original cars the were in. 1 was from a 72 240. & 1 is from a75 280 with an r200 differential. They getting closer to being scrapped.

My Z is 7/71. Does that make it "late"? And of course its a "factory automatic".This is my first Z, so I'm not as educated on these as some of you are. I don't think I will change the diff, so I'm starting to lean towards the 5 speed. And I do plan on doing trips with this car, so the extra gear would definately be a plus. So, exactly where does the 5 speed trans come from. I've read many threads about 5 speeds from late z's and i think some newer Nissans. What is the easiest 5 speed swap with as few mods as possible, and what mods are needed? Throwout bearing? Starter? Driveshaft? Mounts? Console? Also, What are the years and models of the cars that the 5 speed should come from, or the model # of the transmission? I'd rather hear direct answers to these questions than count on info from random threads. Thanks again. Chris.

http://www.classiczcars.com/forums/articles-our-members/21274-240z-260z-280z-auto-4-5-speed-swap.html

Details for your situation - Your car is a late-71, but would have still come with a Type A transmission if it were a 4 speed car. You will probably want to find a Type B 5 speed from any non-turbo '77-83 280Z/ZX. (You could hold out for a Type A 5 speed, but they are rare and expensive here.) With the Type B you will need to either enlarge the tunnel opening or have a custom shift lever fabricated.