300zx vibration

[Azazel703]

I'm having a vibration when I take off from a stop I can fill it in my seat once I get moving the vibration dies down but is still there a little it also goes away when I press the clutch or put in neutral I've checked the carrier bearing but it looks good. And a couple days ago I noticed that after took off from a stop there was a squeaking noise that sounded like it was coming from the rear of the car but now that has gone away and the vibration has started

[evildky]

Could be a U joint in the shaft.

[Azazel703]

Could be a U joint in the shaft.

The u joints seemed to be ok there hardly any free play in them.

[KDS_cars]

bad transmission bushing maybe? letting the clutch out and starting off maybe making the trans shake then as speed it smooths out. I had some vibration issues with mine and turned out to be motor mounts. just a thought.

[evildky]

Subframe bushings?

[DCaff300ZX]

Also possible is a sticking caliper, my passenger rear made the same noises and such as you reported for a few days after sitting for so long/cold weather, but with my Z now pushed back into daily service it then cleared up and hasn't been an issue since, now about 2 weeks.
I've had to clean/service my rears once and the fronts twice since I've had the car, fluid changes and removal/cleaning of the caliper pistons and bores especially...perhaps that's your issue.

[Azazel703]

I think it's my u-joint one is bad on the rear half driveshaft