# Whining Diff?



## strickaj (Oct 25, 2010)

What's up every one.

I'm trying to track down a whining noise coming from the front of the car. I only hear it when I'm going 80km or faster and mostly when i'm on the gas, but not all of the time. At first i thought it was a turbo because it would whine about when i hit boost. About 2 weeks ago i was going about 120km, it started whining, i slowed down to about 70km and noticed that the trorque gauge was stuck at about 5 and i started to smell (ATF or power sterring fluid). I checked the front diff today I opend the top plug. I thought the fluid should be just level with the hole, but it started flowing out. Is it over filled? I also checked the transfer case, it barely trickled out. The transmission how ever I could put my whole finger in and didn't feel any fluid, but the walls were wet.
Any body got any suggestions? I'm trying avoid taking it to the dealer.









I opened the top plug of the front diff and got soaked with fluid. Is that the correct one?









This is the transmission plug I opened and couldn't feel any fluid. Is it low or am I way off?


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## freakazoid3 (Jan 19, 2008)

The diff will probably been a bit overfilled, doesn't really matter if it's just a bit. And yes your gearbox oil probably needs refreshing if you can't feel the level through that hole...


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## strickaj (Oct 25, 2010)

ok thanks Freakazoid.

I have a better description of the noise. It is speed and power related. It's is a steady frequency at any given speed but gets higher pitched the faster I go and gets louder the more gas i give it. Also it cuts out when I go over a hard bump. 

Any idea's? How can I further isolate it?


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## freakazoid3 (Jan 19, 2008)

Sounds like your gearbox to me...Check that one first, might be a bearing in the gearbox on it's way out...


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## strickaj (Oct 25, 2010)

I'll try refilling the gearbox. I'm try to find a vendor that will ship redline shock proof out to Japan.

Thanks


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## freakazoid3 (Jan 19, 2008)

I'd drain the box and first put normal 80W90 or 75W90 stuff in. I'm not a fan off the shockproof stuff anymore since using it myself...

Just my 2 cents


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## strickaj (Oct 25, 2010)

Well the redline is already on the way. I'm not hoping for any miracles, but i figured i would give it a shoot. So is a rebuild the best option or do most people just find a good used transmission to replace it?


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## strickaj (Oct 25, 2010)

Ok at first I thought I was crazy but now I'm sure that the noise goes away when it's in 2wd mode. I have a wheel sensor going bad and it cuts off the 4wd every now and then. When I'm driving in 4wd it whines away, but soon the 4wd cuts off the whine slowly fades. 
What could it be?
On the first post I said about the torque gauge being stuck and smeeling atf or gear oil. but nobody mentioned that and it hasn't happened since.
I have been advised that it could be the transmission, wouldn't that whine weather it's in 2wd or 4wd?


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## strickaj (Oct 25, 2010)

Forgot to mention that it whine at about 50 or 60km now.


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## Tobie (Apr 22, 2009)

I will drain the front diff, take the cover of and check the condition of the diff gears, mine had the same symptoms.



I had to get new diff crown and pinion gears plus setting the backlash and bearing preload with shims


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## strickaj (Oct 25, 2010)

Ok I opened up the diff case and this is what I found.












































I also noticed about a 1/4 inch of play in the drive shaft.
Any ideas what would cause this kind of wear?


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## Ultimategtr (May 29, 2007)

Hey mate, just did this on my 32R. Was whining like a wife. Only did it in 4wd mode.

The inner bit(crown?) was glazed as well. You can see the real shiny bits on the teeth. I'll take some pics of the old diff sometime and post up. When I drained the oil, there was around 1 tsp of shiny metallic 'sand'.

Swapped the Pinion and crown with another working one and can confirm the whine has gone away.

Suspect previous owner had driven it with no/low diff oil. Cant think of anything else that could cause it.

BTW - That was 1 b!tch of a job. Did it on Axle stands, but would have been MUCH MUCH easier on a hoist.


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## jnoor (Feb 24, 2016)

I have a whine from my car as well.

Was told it's the turbos but I don't think it is and after reading this I'm quite sure mine is from the gearbox too.

Will have to drive it this weekend but from memory the whine always comes on when I speed up past 30mph or so.


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## Ultimategtr (May 29, 2007)

Are you sure its not tire noise? Mine started to whine roughly at that speed too.

If you have a R32, pull the fuse out and run it in RWD only and see if the whine is still there.

Is there any metallic bits in the oil?


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## Supertec (Jun 5, 2014)

Whine could be input shaft bearing if coming from the box. Could be many things.


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## jnoor (Feb 24, 2016)

No definitely not tyre noise. Almost resembles a supercharger whine and gets louder as you speed up. It's not deafening, just a subtle whine that is noticeable.

I was thinking if I replaced all the synchros and bearings that should rid the noise.

Clutch release bearing is on its way out too.

What do you think?


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## jnoor (Feb 24, 2016)

If the whine is still there when running in RWD drive only does that point to the gearbox then and away from the diff?


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## Ultimategtr (May 29, 2007)

You didn't answer my question - Is there any metallic bits in the front diff oil? How old is the oil? When I dropped mine, I saw a small heap of metallic 'sand'.. It was super fine stuff.

Mine sounded like the transmissions you hear on race cars, straight cuts/sequential, or whatever they run.

Release bearing wont make that whine. If the whine's still there in RWD ONLY then could be your gearbox, or even your wheel bearings and CV joints. 

Unfortunately its a process of elimination where you would probably start from the cheapest/easiest idea first. From what you say though, it sounds like the front diff to me(my 'expert' online opinion  )


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## jnoor (Feb 24, 2016)

I havent had a look at the front diff and dont exactly know how old the oil is. Has full service history but it's all in japanese and Ive planned to try get someone to go through it for me to know exactly what was done when.

I've likened the sound to straight cut gears too.

I know the clutch release bearing wouldnt cause the noise, just mentioned it as it is on its way out. Rumbles slightly in idles and goes away when the clutch is pressed.

I haven't actually done anything in terms of inspection to start finding the problem so i think i should do that. Just wanted to gauge an initial idea from you.


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## jnoor (Feb 24, 2016)

Btw the whine you had, was that due to the diff too and the 'sand' you found in the oil? What did you do, clean the diff and put in new oil?


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## jnoor (Feb 24, 2016)

Ignore the last message. Read further up the thread on what you did to rid the noise.

I'll try the RWD only driving on the weekend and, if needs be, check the diff and see what that looks like.

Thanks for the help, really appreciate it.


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## mrpete32 (Apr 11, 2021)

Hi guys, 

FYI, you can disable FWD on a GTR while driving by turning the ignition key to off then on again. CAUTION to do it in a straight line to avoid the steering lock from engaging. Once you have disabled the FWD you will notice on the dash that the 4WD light warning light is now on and you will have also disabled the ABS system.....so treat it with respect  NOTE when you come to a stop the system will automatically enable 4WD again. Yes you can permanently disable 4WD by pulling the fuse and the same effects happen to ABS etc.

I have a similar whine in 4WD mode and when I perform this trick it goes away. Yet to be confirmed but my suspicion is that it is a transfer case issue because if it was a front diff issue the noise would still be there as is continues to rotate while the car is rolling, if you get my drift.
I have not ruled out the diff but as I say, it does not add up why the noise would go away in RWD only. 

Food for thought. Mrpete.


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