Grinding Noise Lhf Of R32 Gtr

[SSHatch]

Wasn't sure which section to post this in so figured I would start here and see where we get to.

When I picked up the GTR a couple of weeks ago I noticed a grinding type noise coming from the LHF corner.

Didn't pay it too much attention at the time as I simply wanted to get out of Melbourne in one piece.

Got back to Tassie and took the car into work and threw it up on the hoist to have a look but there is nothing obvious that would be making the noise.

Its a rotational noise, occurs pretty much as soon as the car starts moving. Its not affected by brake application, clutch in or out, in gear or out of gear. Initially I was thinking wheel bearing but I have never heard one make a noise almost immediately the car starts moving. Were talking simply rolling forward down a slight slope is enough. The noise doesn't have that deep graunch type noise that you would expect to hear with a wheel bearing either. It sounds more like something rubbing against a rotating component.

This led me believe that the massive lips on the rotors could have been the cause where they were rubbing against the pads. Took them off last night and machined the lips off the rotors but the noise is still there.

With the car on the hoist and spinning the wheels by hand the noise does not seem to be there which makes me think again that its a bearing of some kind and needs the load of the car on it to produce the noise.

I also thought it could be the support bearing on the LH drive-shaft where it passes through the sump. My only issue here is that I have not heard of many of these bearing's failing on any cars. Spoke with the guys at our Mitsubishi workshop and they agreed that its possible but they have had very little issue with the Magnas that run a similar setup as the bearing is mainly there for support and does not take that much load.

So any suggestions as to what it could be. As far as I know I have checked most rotating components to make sure they are not contacting something that may cause this noise. Anybody had anything similar?? Suggestions??

I could just throw in a new wheel bearing and drive-shaft support bearing and hope it fixes it but its a lot of money in parts for a guess.

[No Crust Racing]

I'd be thinking wheel or drive shaft bearing as there's not much else in that area that will make a rotational noise that you haven't already checked. My first guess was rotors but you're confident that's all good.

Good luck and let us know what you find.

[YLD-CHLD]

are the cv boots cracked in any way?

sounds like u have a cv problem maybe.

[No Crust Racing]

Actually that's a really good point, outer lefts are notorious as they do a lot of work.

[SSHatch]

I suppose the CV theory has some merit.

That could explain why the noise is heard with the car on the ground and not up in the air with the suspension dangling. The angle of the shafts would alter dramatically and could mask or alter the noise.

Pretty sure the boots themselves are all OK but that's not to say there isn't an issue lurking behind them.

Might head out to the garage and investigate that option a bit further.

Oh and Dan... Wodonga. What a town. I spent a few years there in the late 80's. Had a hell of a time. Still got family there today.

Must head back and visist again see how much its changed this time around.

Edited November 18, 2008 by SSHatch

[GTR-N1]

Sounds like the Drive Shaft to me even if the boot isn't cracked (because at some stage, the boot may have been replaced already).

Does the noise worsen if you make a right hand turn into a rise?

[SSHatch]

Noise is pretty constant under most conditions. Does get a little more audible when turning but nowhere near what would be expected from a CV Joint (which is "usually" more of a clicking noise from experience) or a wheel bearing.

I should also point out here, not to be a smartass or anything but so that people realise is all, I am a mechanic by trade and have been involved in the car industry for 10 years or more now. Not saying I know everything but so that people know they arent trying to help a complete noob here. Just somebody who has done all the normal workshop stuff and is still a bit bamboozled by this particular noise.

And I dont particularly wanna throw heaps of my hard earned at this hoping to fix it.

In all honesty it sounds like the kind of noise you hear when the brake pads are worn down to the backing plates. Its real distinct metal on metal grinding kind of noise, not really anything like you would expect a bearing to sound like and doesnt alter like wheel bearing and the like do when you load them up going round corners etc which is why I asked about the LH driveshaft support bearing.

It very well may be a bearing but in all my experience a bearing sounds different.

Keep the suggestions rolling guys, I am pretty lost at the moment and looking into everything you suggest.

Edited November 20, 2008 by SSHatch

[Moshi]

Noise is pretty constant under most conditions. Does get a little more audible when turning but nowhere near what would be expected from a CV Joint (which is "usually" more of a clicking noise from experience) or a wheel bearing.

I should also point out here, not to be a smartass or anything but so that people realise is all, I am a mechanic by trade and have been involved in the car industry for 10 years or more now. Not saying I know everything but so that people know they arent trying to help a complete noob here. Just somebody who has done all the normal workshop stuff and is still a bit bamboozled by this particular noise.

And I dont particularly wanna throw heaps of my hard earned at this hoping to fix it.

In all honesty it sounds like the kind of noise you hear when the brake pads are worn down to the backing plates. Its real distinct metal on metal grinding kind of noise, not really anything like you would expect a bearing to sound like and doesnt alter like wheel bearing and the like do when you load them up going round corners etc which is why I asked about the LH driveshaft support bearing.

It very well may be a bearing but in all my experience a bearing sounds different.

Keep the suggestions rolling guys, I am pretty lost at the moment and looking into everything you suggest.

Mate first of all i would like to say since you have a gtr then you have 4wd system

Firstly disable 4wd...you should have a switch if not just plug out 4wd fuse then your front wheel should be disengaged not 100% sure because i only have gtst

Then chuck on hoist and try to rotate lhf disc when rotating, rotate the studs and try to feel and disruptions in the movement, if there is no disruption then it just might be

The dust cover plate that is touching the disc. Check the metal dust cover plate properly to be sure theres equal gap all round. If you cant see gaps in certain places, then thats where it rubs against the disc. Metal plate to rotating disc contact = grinding metal noise

I am not a mechanic but i just wana help out it just could be a possibility.

Take it easy mate

Cya