Whining gearbox, only in 1st gear and not in neutral coasting

[Mikevv]

Hi guys, recently I noticed my Z is making a weird whining noise at speed in first gear.

I know this seems a bit specific, but if I go above say 20 mph in first ( like pulling out at a junction quickly to take a gap ) it makes a weird whining noise, that's relative to revs so it seems, or maybe more speed?

 

I ignored it at first and thought it was just me hearing things, but now my brother was in the car today and he heard it too, and I stayed around 40 mph and went through all the gears, nothing. Then tried 60mph in the various gears, to get the revs a bit higher and just roll. Again nothing.

 

I slowed down, and gently drove away in first and sped up, gently, and it began around 20-25 mph. It made the noise when the clutch pedal was fully down and just rolling ( as if to change gear, but staying in first ) The very moment it was out of gear, and in neutral it stopped. I put it back into first again, and the second the car engaged the gear the noise began again.

 

As I said, it's not in any gear, only first.

 

It sounds like a whirring/spinning noise. Could it just be the gearbox making normal noise, like the gears spinning? Am I being paranoid? My logic is that if that was the case, surely it would do it in all the gears at roughly similar levels of stress?

I will check the various receipts from the previous owner ( FNSH ) to see if it has had fluids changed, otherwise could that be my next option?

 

I want to get this fixed soon, as I only have 2 months warranty left ( owned the car for a month now ) and I doubt the dealer I bought it from will accept responsibility.

[Grundy]

Input bearing.

[Mikevv]

My very limited knowledge and googling suggested this at one point, but I wasn't sure.

 

Is it a big job? What about parts?

 

My brother in law is a Honda master mechanic, one of <100 in the uk, so he will be doing the work as I trust him, at work.

We have no place ourselves to do it, and at work he as all the tools and ramps etc so why not

 

Sorry, I'm a young newb and love cars but never got any experience as nothing ever broke ( lucky me )

 

I'm just thinking is it worth phoning my dealer up, its a 250 mile round trip there and back. My issue is it will actually be 500 miles cause I'd drive up, drop the car to be fixed, drive home, and then come back a week later. Might be easier to bite the bullet myself and what I spend in fuel just use for the service.

Edited September 1, 2015 by Mikevv

[Juggalo]

Mine did the same only in first gear. Took it to the Gearbox centre and they stripped it. Gearbox was beyond economical repair, so had to buy another.

Hope yours isn't that bad.

Edited September 1, 2015 by Juggalo

[Mikevv]

Now we're leaning towards syncro rings, again main issue seems to be first.

Any idea how long it would take to switch out and what sorta costs for parts,both for and input shaft bearings.

Need a nissan tech to listen but I hear ( no offence to any) they're useless on Z cars/GTRs.

[Grundy]

Couple Hundred quid from a competent garage. requires dropping the gear box.

[Mikevv]

Took it to a garage today, was told basically my thrust bearing is starting to wear out.

 

I'm phoning the dealer on Monday and saying look, it's no worth only replacing the thrust bearing, do all the bearings and we can work out what's covered by warranty.

 

Does this seem fair to you guys?

Or should he cover just the thrust bearing and input shaft bearings, and I pay the rest? Obviously I would get this in writing first before doing any of it.