5spd vs. 4 spd visual difference?

[stewsjunk]

Need some help from the experts. Is their any visual differences in the 4 or 5spd units??

Thanks for any help

[ZSaint]

Here is a pic of both trannies. The 5-speed has a larger/longer case.

[Walter Moore]

BTW, the 4 speed in the previous picture is from an early Z car. (70 - 71)

The late 4 speed looks like the transmission on the right in ZSaint's picture. The 5 speed is longer however, and takes a different drive shaft. At least that is what the Hanes manual says, I have never seen one.

I just know that MY 4-speed looks like the transmission on the right.

[ZSaint]

Here is what the 5-speed looks like on the INSIDE. This is the rear unit for the 5-speed. It will tell you whether you have a 4- or 5-speed.

The 4-speed came out of a 2/71 '71 Z. The 5-speed came out of a '83 Maxima. I used the original driveshaft (w/new u-joints) when I installed the later 5-speed.

[Darrel]

This is the later 4 spd, note the height of the pivot hole

Early 5 spd. note the lentgh of the shifter ears and height of the pivot hole

Late 5 spd, note the longer length shifter ears and the height of the pivot hole.

If you have a late 5 speed you can make a short throw shift mod without paying the $150 for the msa short throw kit. Redrill the longer ears on the shifter ears on the tranny then cut the bottom portion of a 4 speed shifter and drill and tap for a stud to lengthen. Check out the pics in my gallery for the mods.

There are other differences but these seem to be pretty consistant.

[sakijo]

My 5 speed was shorter than the 4 speed it replaced. Might be a JDM thing. Look in my gallery for side-by-side comparison.

[Darrel]

My 5 speed was shorter than the 4 speed it replaced. Might be a JDM thing. Look in my gallery for side-by-side comparison.

There seems to be so many differences in transmission types between US spec and other markets.

The top one could have come out of another car requiring the need for a shorter back half or it could be the 5 spd boxes that were in the other markets and never made it to the US market.

Is the 5th gear 1:1 or is it an actual overdrive?

[ZSaint]

They come both ways. The comp box was a direct-drive 5th gear. It was developed for higher horsepower engines. My '83 5-speed is a .745 O/D. The ZX's came with a .830 O/D or somewhere close. I went with the longer O/D with my 3.9 L/S R200. I do not know if you can find one of these older trannies with the D/D 5th gear. I have never seen one advertised. I guess they were used up by the old racers!

[240ZX]

My 5 speed was shorter than the 4 speed it replaced. Might be a JDM thing. Look in my gallery for side-by-side comparison.

I'm with Miles.....the 82-83 ZX 5spd I installed in my 1970 is certainly shorter than the original 4spd. I had to remove about an inch from the forward portion of the tranny tunnel, where the shifter comes out, to get the clearance I needed. However, I believe demensions changed in late 71 and for 72 models....not certain on this though!

[ZSaint]

When you say "shorter" do you mean the shifter is shorter (closer to the engine?) and you need to modify the tunnel? What about the driveshaft? Did you need to shorten it? I am curious about this "shorter" 5-speed.

[sakijo]

My car is a Skyline, not a Z, but a lot of the parts interchange. The short 5-speed required no modifications and bolted right in. I don't know what it came out of, but my guess would be a Z. It is a true overdrive unit, .830 as ZSaint mentions. Works well with my 3.90 rear end and re-ground camshaft. 1:1 5 speeds occasionally pop up on Yahoo Japan, but the sellers know what they have and price accordingly. I got my trans for a song . . . .

When you say "shorter" do you mean the shifter is shorter (closer to the engine?) and you need to modify the tunnel? What about the driveshaft? Did you need to shorten it? I am curious about this "shorter" 5-speed.

I believe he means that the shifter location was further forward than the original one. Thus, he had to cut the opening of the tunnel where the shifter comes out to make it work. There are different shifters as well, a straight one and a bent one. Assuming that he had the straight one, if he had a bent one, maybe he didn't need to cut the tunnel opening. It was th opposite for me, bent one no good; straight one ok. The driveshaft should be ok, no modifications on mine.

[ZSaint]

I also had to modify the tunnel for my 5-speed. The tranny is the same length as the 4-speed. The only difference is the shifting mechanism. OK... We have that solved!