Brand new gearbox stuffed, nissan says 'too bad'

[ferni]

I've driven probably 1000ks on this new gearbox, so don't think its a running in issue - thanks anyway...

I spoke to exedy, they recon it is the box, gearbox guy recons its the box, mechanic recons its the box... who knows...

I can't logically think it could be the thrust bearing - maybe if it was a push type clutch, but not a pull type - there is noething for it to rub against etc... and the load on the thrust is when you push the clutch pedal down... which is when my noise goes away... doesn't make sense... but we'll see...

[ferni]

Got the gearbox out this morning. The input shaft was a bit dry, couldn't see where the grease went. The box came with the input shaft already greased up - maybe it was to old? But i think thats what was causing my clutch to catch sometimes when downshifting... still not sure whats causing the noise tho. Box is going into Nissan on Monday.

[nothing]

I'm very interested in this thread, please let us know the outcome ferni.

[ferni]

Ok got a call this morning from my Mechanic... Nissan called him, told him that they have fixed it.

They say it was a 'reverse idler gear' It supposedly had burs on it... They have replaced the part, and put the gearbox back together. Mechanic spoke to his gearbox guy that i took my car to to let them listen, they said that makes sense and it's very likely that was the cause of the noise...

Should be putting the gearbox back in tomorrow night hopefully..... fingers crossed this whole thing is sorted out now (and hopefully Nissan didn't break anything else while they were in there)

[Ronin 09]

excellent, good luck!

[Kel]

Hmmmm- not to go too far off topic but I've had nothing but troubles in my dealings with Nissan on things that have gone wrong on the Zed (yep, a 6 month old car).

Best of luck but I've had them tell me they've *fixed* numerous problems at least three times- worst of which is a horrible clunk in the steering. The noise was still there as I drove out of the dealership on my last visit (which had convieniently shut for the day!).

They also told me loose wiring in the passengers door speaker was my imagination, before finally looking at it and telling me they'd fixed the problem (you guessed it, it still cuts out over bumps).

IMHO- Nissan have no idea how to sell or service anything other than pulsars and patrols these days.

Hope they've got your problem sorted!

[ferni]

Kel: Dealerships are individual businesses, maybe try taking your car to another dealership to be serviced/looked after?

In fact, the Parts department and Service department are completly seperate too... My mechanic is friends with the guy in Ferntree Gully Nissan Spare parts... he's been very helpful pushign this through, but he has no control/say int he service department...

But you're right i'm not holding my breath that the box is fixed, but if its not, they're gonna cop hell, and my mechanics going to start charging them for his time - which he has warned them.

Thanks for the input kel.

[Kel]

Andrew, I'll definitely take you up on that advice and keep trying! Unfortunately I've dealt with two locations so far and seem to get the same apathetic approach : (

I really hope they've got yours sorted out though!

[ferni]

Kel: usless pricks! if you haven't already - ask friends/family (NSW forum?) for a 'good' nissan dealership in your area...

I hope my box is sorted out as well, i'm about to go crazy, all this on top of buying a house is just too much!

[ferni]

http://auto.howstuffworks.com/question522.htm

Some info on a reverse idler gear....

Anyone know what exactly they are for, and why it would make the noise in neutral ?

[ferni]

Ahh found it,

http://auto.howstuffworks.com/transmission5.htm

the purple bit labeled 'idler gear' must be it since it is always spinning /engaged (not selected) it would always make that noise, just more noticable in neutral when there is little engine noise.

[ferni]

Now i'm worried, what damage could the burs on that idler gear caused the other 2 gears it is in contact with? what if there were other bits of the burs that came off and floated around in my gearbox...

How can they justify me paying full price for a gearbox that could be damaged/worn - may as well of bought a 2nd hand one...

I don't think its fair i pay full price for this - either that or they should give me a brand new box... what rights do i have here?

[Cubes]

That noise is most definately not the thrust bearing.

I have had my 20t box for almost 3 years now and it is as noisy as yours.

In first & second you can gear it whine, 5th on light throttle you can play with the noise.

This is the important bit here.

On light throttle up and down you can change the noise & sound slightly.

If it were the thrust bearing the noise is constant and cannot be manipulated by load.

Its the box.

I always thought mine was the most probably the input shaft bearing but hey it could be some other bearing.

Mine is also rather lound in reverse. Louder than the average manual.

[ferni]

Joel: Maybe its the same gear as mine, 'reverse idler gear' ?

ahh well

[Cubes]

I have heard quite a few RB20DET box's make the noise. Never a GTR.

Mine is super loud. If you head through Mc' Donalds etc I always dip the clutch as its embarrassing.

People on the Mic Phone at Hungry jacks some times have trouble hearing me if the clutch is out. :Oops:

People always refer to it as the input shaft bearing.

I wasn't aware the RB box's have a idler?.. I always thought it was a simple main shaft + a lower layshaft setup. No gears inbetween.

[ferni]

Joel: Mine is embarrising too when its rebounding of a car or a wall next to you.

Yeah people were telling me it would be the input shaft bearing, but supposedly they checked all bearings etc.. and it was all fine...

This idler is for reverse - it would need a gear in between the layshaft and main shaft to reverse the gear ? otherwise it would just be another gear.

[Cubes]

Its probably also a little to do with the endfloats.. Maybe it was setup incorrectly from factory causing the perfect bearing/gears to sound a little noisy?!?

When I had the front cover off my box to replace the input shaft bearing seal I noticed within the front cover there is a thin metal shim. Depending on the thickness of this shim made a big difference to how noisy the g/box was.

The shim was only on the lay shaft bearing. I am unsure if the input shaft bearing was supposed to have one. Maybe thats where my noise is coming from.

Too many variables and I don't know whats what.

Its either the bearing or the shim/gapping has been setup incorrectly.

The GTR box could be different with regard with the shim but you get the rough idea.

[Cubes]

I've got a mp3 of what mine sounds like.

The camera was placed on the ground just as I open the car door, so its not under the car. It doesn't sound as bad as yours though. Probably due to the idling rev's.

Mine was idling around 650rpm, raising the rev's to 1100rpm.

Hear the RB30 purr.

[ferni]

my wav file was taken from exact same place on my phone.... mine idles around 1000rpm

[ferni]

doesn't sound as loud as mine, but hard to tell...

half way through putting the gearbox back in now, nearly done, just doing an oil change as well and a couple of other things