My Z is a 2005, 6sp MT. The transmission shifts very smoothly. However whenever I shift at about 4500 RPM or above, there is a 'thunk' noise for every gear. It's definately NOT grinding. It always happends when I POP the clutch. I think it's the noise of the transmission engages with the engine. So is it normal to hear this 'thunk' noise or the car is supposed not to make a noise when shift at high RPM?? thanks guys

 

I would say normal. It definitely isn't the quietest gear box in the world.

 

New to the thread, I have the same thing going on when I clutch kick I get a thunk noise from what it sounds like the diff but if normal then awesome.

 

This has happened to me before when running it over 5000 rpm, the first time it scared the **** out of me, but it's not a problem.

 

Let off the gas then accelerate; noise still present?

 

I love how you guys beat on your cars and then wonder what the "thunk" is from. How about learning to match revs and shift smoothly? Or, just buy a Mustang.

 

Our tranny sucks and not only makes a lot of noise but is quite clunky.

 

I fail to see how shifting at 4500 rpm is "beating" on a car.

 

Maybe it's a bad engine or transmission mount.

 

Easy to blame the car. I've been driving MT cars for 40 years, and don't find anything to complain about with the 350Z gearbox. Smooth shifting may require some patience and practice, but will become second nature at some point. The Z's drivetrain is not without flaws, especially the hydraulics in the HR cars, but the gearbox itself (even the pre-CD009's) is pretty solid.

 

It's not. I'm not concerned about the engine revs, but smooth shifting requires matching the engine revs to the car speed and selected gear. If you're upshifting, you need to let the engine revs drop while shifting, and conversely you meed to blip the throttle and increase the engine revs when shifting down. OP mentions he "pops" the clutch, rather than releasing it smoothly, and that statement alone hints at a basic misunderstanding of how to drive an MT car. Shifting smoothly not only preserves the components involved, but it's also conducive to better dynamic balance when the car is near its limits. Go to a vintage racing event (i.e. racing involving cars without electronic paddle shift gearboxes), and listen to the fast guys and how smoothly they drive. You won't see anyone pop the clutch powering out of a corner or downshifting onto one, and you'll hear every shift with proper rev matching between gears. Hell, you can even drive next to a semi-truck on a hilly or curvy interstate highway and listen to how the driver carefully rev matches each shift. Imagine the gearbox has no syncros, and if you get your technique perfect, the shifter just slides into the next gear as smooth as silk. Any resistance or extra force required means you need more practice.

 

no just when i clutch kick

 

does it sound like its coming from the back?

 

Idiot.