My 1985 300zx NA will not shift out of what i believe is fourth. I just replaced the clutch and slave cylinder with a new master on the way. The slave cylinder travels fully and the clutch doesnt feel too wrong. The shifter has no give at all and will not even attempt to disengage gear. I can hold the clutch in and start the car, and if i let it out the rear wheels do spin. When i drained the tranny no bits came out so hopefully it isnt exploded. I've heard shift linkage, master cylinder, and pedal free play. Any additional input that could be helpful?

 

It's obviously not the clutch since it disengages and engages with the pedal. I would guess it's something in the tranny. I would try bumping the clutch while trying to free the shifter...rev the engine a bit and begin to engage then shove on the shifter as hard as you can while disengaging...it might come out. Otherwise you'll have to pull the tranny I suppose.

 

Your linkage inside your transmission is broken. You have to drop the tranny again and open it up.

 

I pulled the transmission apart. Very interesting problem. It was not the linkage or any clutch related component and no parts inside the transmission had failed. The syncro was actually forced too far into gear and for some reason the syncro keys popped up and locked it into that gear. Once i pushed the keys back in and slide the gear back into neutral position, i never had the problem again. Too bad this happened after replacing clutch, throwout bearing, master and slave cylinder, and clutch line. Fun stuff.