Tip to diagnose a driveline whine

[milkandoj]

Ive noticed a wine lately and yesterday i swear it has gotten louder. To me it sounds like bearings or something similar on the way out.
It is dependent on load because its louder if im on or off the throttle, and coasting its much softer.

I can hear it loudest taking off in first as the exhaust and induction noise it so loud but it think its there when cruising faster. Almost sounds like hearing a strait cut gearbox but softer.

Having a look around i noticed the bushes that hold the drive shaft are sloppy so i was going to get onto that, so i'm thinking possibly the carrier bearings?
How would i go about trying to diagnose this.

I'm hoping the transfer case isnt about to let go as that could be dangerous.

Come to think of it ive done a few antilag launches smoking the tires haha lately,and i recon its gotten louder since ive done that. I should switch it off and just run the stutterbox. Sounds so freaking cool though.

 

[bazeng]

Carrier bearings are usually quite sloppy anyway mate. I get the opposite. Quite on load but loud on decel. What clutch do you have? Solid discs trend to transmit all the vibration and noise to the rear of the car. Just make sure your fluids are topped up in the xfer case. They take barely any oil to begin with and if you haven't done that yoke leak fix it could be running low.

You would be surprised with how much mechanical noise a loud exhaust hides.

 

[milkandoj]

I Checked the oil in the transfer case and gearbox and its fine.
This noise has recently gotten louder, so i want to check it out. Sounds like a strait cut gearbox sound almost.
The idea of the transfer case seizing at 100km makes me nervous, so i want to find where the problem is.

 

[brisvr4]

What did the transfer cae oil smell like Gerard?
It's also possible that there is a bearing on it's way out in the gearbox too.
My guess is a bearing as it's louder under load and fairly quite coasting with no load.

 

[Rockabilly]

I sheared the shaft at the crown wheel end of my previous lsd in one of my auto boxes.
If this has happened in yours, you could have Bad meshing of your crown to pinion.
It would be louder on deccell because of the direction of the gears. I hope your's isn't this.

Cheers !

 

[EVO-00X]

Its most probably the vibration and noises from the h/duty clutch transmitting through the gearbox. My current rebuilt GSR box makes the similar straight cut noise most noticably on decel. The rest of my driveline is in excellent condition, new oil, bearings etc.

 

[rob323]

Does the pitch of the whine raise with speed or revs? Knowing this will help determine where to look.

 

[MDK87]

The idea of the transfer case seizing at 100km makes me nervous, so i want to find where the problem is.

Yes, that's not fun...

 

[milkandoj]

I just went for another drive to listen, I can hear it in first, accelerating, holding a steady speed, but it goes away when i decelerate.
I cant hear it in other gears. I can definitively hear it distinctly in first however.

 

[milkandoj]

Any ideas if the noise is only there in First gear?
Is there when i accelerate and hold a steady speed, but goes away when decelerate.

(Maybe me and first gear arn't friends anymore?)

 

[omad]

you really need to get onto those engine mounts and carrier bushes before you break something =P

 

[milkandoj]

you really need to get onto those engine mounts and carrier bushes before you break something =P

Carrier bushings yeah, but engine mounts? Swear they were fine when i did the clutch i had a look.