Can anyone give me some advice/tips on upgrading my 4 speed tranny to a 5 speed. I suspect the 5 speed will be from a 77' or 78 280z, although not sure. Is this just a matter or removing the old tranny and putting the new one in?

Some links to a walkthrough or any helpful information would be great.

Thanks in advance!

Depending on how you drive, the 81-83 5 speed would probably be better because of the higher 5th gear. Basically just a bolt in but you have to use matching clutch components.

I'm not exactly sure yet what kind of tranny it is; but it might actually be a ZX tranny; considering the owner owns a 240z (which didnt come in 5 speed) as well as an 81 - 83 zx. Bigger chance thats its ZX version.

I'll let you know when I do.

Doesn't much matter which it is, from an installation viewpoint. Either one is pretty much a straightforward swap into a 280Z. If you are using your existing clutch, use the throwout bearing and collar from the four speed, not the new five speed. You will probably want to use the speedo drive gear from the four speed as well. Other than those things, the rest is a straight replacement.

Also, it is not very hard to change the front and back seals on the 5spd. On the front seal just be careful not to set the seal to deep in its housing. It does not cost alot and is a good preventive measure. Your new speedo cog may have to go into a different housing to match up with the teeth on the tranny shaft. My differential is a 4.11, and I had to turn the cog housing and cut a new flat to hold the set bolt. datsunzgarage.com/engine/ is a good resource for this mod. Jon