So my 95' 300z seems to buck alot when under light load, when I come to a stop 1st grinds, often, but not always. I can put it into 2nd and then 1st and theres no prob, it's as if changing into second shifts the tranny so 1st doesnt grind....
Sometimes during launches, it just feels like the tranny wants to shift back and forward. The bucking can be pretty violent.

Oh, and one more random question:
I hear a loud screaming noise around 125 and up, and I know for sure it's the transmission. It's metallic sounding and there is a little vibration coming from that direction too Should I get new motor oil with a higher viscousity? Is the tranny being starved of Oil? I am kinda skeptical to ask a mechanic from around my area. They would probably just say "well then... just don't drive it that fast". Maybe....

 

yea... anyone have an idea?

 

motor oil??? no no no... manual tranny fluid... synthetic... change your fluid in it there is a plug on the side to fill it from and when it starts to leak from that plug its full.. if 1st grinds and the clutch is all the way to the floor its your synchros... they are going out and will probably need replaced soon. unless you know trannies very well i would just have a profesional do it. as for the bucking... i think that might be somethign more engine related and transfering the motion to the tranny since its all connected

 

is this a TT or N/a? how many miles are on it? does the clutch completely engage/disengage? are your rpms fluctuating when the z bucks?

 

have some patience. you asked less than an hour ago.

 

I meant tranny oil... whoops

 

It is a 95' NA. It has 150,852 miles to it's name.

Yes,The clutch does completely engage.

For some reason it has been doing it that much lately since I've been using royal purple 10w30.

How much are synchros? My friends dad works on stock/race cars... granted they are muscle cars.

Could it be worn engine mounts... the transmission mount

 

and the RPMs fluctuate.

 

time to check the ECU for codes.

 

is the clutch slipping? forgot to ask that earlier

 

hmm.. yeah around 150k i had to change my original clutch.. slipped like crazy. and if RPM's are fluctuating its pointing more towards the engine for the bucking... some what... so check the codes. and i really dont know the prices on synchros. and if you did use the royal purple it will help out on the synchrose temporarily a few thousand miles it will probably start showing up again if it still does it from time to time.

 

well the clutch seems to be good as far as I can tell. I mean, I can shift at high RPM, and shift quickly in all gears and not slip or grind, except the 1st gear thing. I will check the ecu... thanks, lot's of good ideas

- does any know about high mph tranny noise?

 

the rpms only fluctuate when bucking is occuring. The clutch was replaced @ 85,000 miles. The previous owner had it changed, i have papers.