Diff noise

[JustCallMeOrlando]

Hey all,

I've had no stereo since I got my car on the road...it's been over 6 months now. That's a moot point though. What it has made enabled me to do is hear all the sounds my car makes.

I've sorted the exhaust, but one that is bugging me is the diff. It was rebuilt with new bearings when the Truetrac went in, but it's just, well, noisy. Not in a "sounds detrimental" sorta noise, just a bit whiney. When you're off the throttle it's fine, when you get on the throttle lightly you can hear it, especially cruising. Push a bit harder and it tends to go away a bit, that or the cars other noises overwhelm it. The diff itself is tight as, feels great.

I was glad to find it wasn't just me, CrUZida's diff does it as well. Enough background, my question is, is there anything that can be done to reduce the noise? I'm unsure what oil is in there. CrUZ is using Penrite Sin. Is it just something i'm going to have to put up with, and just deal with the fact it's just the gears being old and a bit worn? Does anyone elses diff do it?

Can anyone recommend anything I can do to perhaps block a bit of noise from entering the cabin? I've sprayed the passenger area floor with body deadener, I didn't do the boot though, but there is a false floor and a layer of carpet and foam I thought might help a little.

Cheers,
Nathan

[love ke70]

my ke70 does the same thing, i know its a completely different car but i have the same symptoms. usually only above 80 or so kliks. i figure its just the wear, and yeah mine does at cruising speed, load it up and it tends to go away to a certain extent.
any ideas on how to reduce this would be tip top

[Draven]

hrm... I never noticed my diff making a whine..

[Smokey228]

my diff made a few whining noiises, thne it self destructed. upon removal there were pretty metallics all through the nicely burnt diff oil

but i put a new diff in now, all nice and welded, and i still get the noise. so i figure its the box, throwout bearing is worn a bit. underload it goes away, under strain, wow, its incredibly noisy...
so this is deffinetly ur diff then? if it is deffinetly not ur box, then i would say its most likely bearings... but if its jus rebuilt i would look into it a bit more, cause u wouldnt expect them to wear that quickly...

my 2c...

[JustCallMeOrlando]

My RA60 makes a similar noise, I think I might just have to put it down to age and wear on the gears. Definetly not the box.

[Norbie]

My old diff used to whine like a bitch thanks to incorrect pinion pre-load. Current diff is nice and quiet even after a couple of years of Norbie-style abuse. Maybe the diff shop set the pre-load a bit tight?

[JustCallMeOrlando]

Hmm, methinks I shall have a word to him.

[Draven]

"To do a Norbie" (adj., verb) - to drive in a manner suggesting an intense hatred of your car, and a concerted effort to break the weakest part

[Big T]

I'd vote for pinion as well. My cousin's diff currently has a farked pinion bearing and the thing whines VERY loudly but only under load. Off the gas and it behaves as normal.

Eddie.

[RPM016T]

Try heavy duty gearbox/transaxle fluid. I thinks it be 90-110w rather than 80w? Helps a bit.

[kingmick]

nathan, its prob just worn gears! when the clearances open up they get a whine!check lash. can also be the bearing getting freeplay in it so it changes the lash a bit on and of power.
have you changed the oil at oil?

[JustCallMeOrlando]

Yeah, the oil was changed about 7-8000km ago when the Truetrac was put into it. Bearings were changed too. I'll still ask him about pinion pre-load, but aside from that it looks like i'm just going to have to chalk it up to wear on the gears.

[kingmick]

yep! if you have just done all that its def gear wear! haha cant be worse than some of the locked 9inch ones that ive driven on the track! i swear ford put a whine in them from the factory, just so people new they are big diffs!lol

[82MKII]

Nathan,
mine does the same!!
The noise is worst at about 70km/hr and under light throttle/overrun.
Due to the dodgey seals the diff shop put in when they installed the truetrak - I have had it back to them three times (they finally fixed it). I have asked them to check it and each time they reckon the preload is ok.
I reckon you just have to put your stereo back in!!

Regards

Peter

[JustCallMeOrlando]

Hah, the RA60 does it too and I notice it only when have no stereo in, you're probably right.