5spd transmission problems

[jp81]

Good evening,

I've recently purchased a RHD 300ZX TT 2+2 and the transmission is giving me some strange problems. It starts happening after I've been driving for 15-20min. When I accelerate quickly from 3rd to 4th it sometimes "grinds". The strange part is when I go from 5th to 4th it grinds, but not if I go from 5th to 3rd (put the stick in the 3rd gear, but not releasing the clutch) and then 4th. I've discussed this with a few people and they seem to think its a syncro problem, but I'd like to know what you guys think! Has anyone had a transmission swap?.... if so how much do shops typically charge to swap one out? Is there a difference in parts when it comes to RHD and LHD trannys?

thanks!
JP

[Metacom]

If you're getting into and out of gears without a grinding noise, to me that'd say the syncros are ok.

If you accelerate in gear with clutch engaged and get a grinding noise id think your gears are roughed up somehow or something in the clutch assembly is making the noise.

Have you replaced transmission oil with quality oil?

In my experience a Z shop charges around 500-800 to drop the transmission.

[jp81]

I have to say that's its quite a weird problem as it doesn't do it all the time. I came back from work today and what I did is took my time to shift into 5th and also downshifted into 4th. I was also giving it a good go in 3rd and had no problems putting it in 4th...but I did wait an extra 1/4sec before I put it in gear. Perhaps I have a transmission with attitude...lol. I think I'll take your advice and have the oil changed with good oil....prob the Nissan oil and see what improvements come out of that. I was thinking that it may be a badly bled clutch too that has some water/air in it which would alter the density of the fluid in the line.

[Metacom]

Someone may have screwed with your clutch pedal adjustment. Its easy to look up under there and check if the pedal is pushing in the master cylinder plunger far enough to release the clutch enough to shift smoothly. http://specialtyz.com/blog/?page_id=178

Check the slave cylinder too located on bottom passenger side of transmission for leaks/operation.

[jp81]

When I went to check out the footwell area for the pedal I noticed some signs of leakage coming from the master. I looked at the reservoir up front and it was almost empty, so I managed to find the clutch bleeding method on here and so far it drives great! I'm taking it for a drive on sat to test it out a little more, but seems like I'll have to swap out the master if it comes back. I'm just happy to see that it wasn't a $1500 transmission job!