Sub-Subaru

I posted last year about my gearbox and got some replies for diagnosis. It seems that the transfer bearings need replacing in my 2004 WRX gearbox.

However, I haven't done this as the garage on here who diagnosed it isn't round the corner from me and there aren't too many other places around here that I know of. I have probably covered about 20,000 since this.

Now I have noticed another gearbox sound and I'm very worried. I don't know if this is as a result of not fixing the above or whether it is something unrelated.

When I am off the acceleration and coming up to lights/going down hill there is this chattering metal noise a bit like a pad scratching on a disk. It is almost like the sound of a dinner plate being scratched in one place. It even does it if I put the gearbox in neutral and roll but doesn't seem to be there under acceleration that I can tell.

Has anybody any thoughts on this...

thanks

poolio74

Are you sure its not the brakes?

Sub-Subaru

No not 100% sure and I've been trying to listen when driving past walls for the rebound sound. However, it has been going on a while and sounds deeper than brakes.

If it was brakes I would have thought after a while the pads would wear down and it would stop.

poolio74

Not always mate. Ive experienced some horrific noises from brakes.

Doesn't sound like typical gearbox noise to me.

AzzDSM

Does the noise change if you put the brakes on slightly?

Sub-Subaru

I'm not sure, I tried to listen this evening but the noise of the rain etc on the road made it too difficult. I will try again over the next day or two. It might reduce but still for some reason doesn't seem 100% brake related to me. The thing that is surprising is that it is quite a slow rotating type noise even when travelling at say 20mph.

Although I don't know much about the internals of a gearbox I can't image what it could be in the box.

poolio74

My guess is your paranoid about your gearbox(transfer bearings) and that's making you think its your box when its probably your brakes.

Cant say for sure but that's where my money would be. Get it up on a ramp and run it in gear, then you will know for sure.

Chibs

Could potentially be a rattling heat shield on the Down Pipe or up pipe too?

ditchmyster

iTrader: (7)

When was the last time you changed the oil in the gearbox?

Sub-Subaru

I will post my findings soon

Sub-Subaru

Hi


I found that the rear pads had worn down a lot and needed replacing. However, that has not cured the problem and the problem sounds like its getting louder.


The noise is only there under decelaration. So when going down hill and on decelaration I hear it, then I slightly touch the throttle to match road speed and it take the load off the gearbox and it stops the noise and under acceleration its fine.

The noise is like the sound of cutlery on a plate, that sort of echo of ceramic. It is very strange.

I am now wondering if this could be something with the clutch or where the gearbox and engine meet? Or possibly the main prop shaft going to the back or something.


Oils in the gearbox and rear diff where changed about 20,000 miles ago.

ditchmyster

iTrader: (7)

I think it's called clutch chatter, mine does it and I too had a problem describing it until yesterday. What it actually sounds like is when your driving fast in reverse.

I'll dig the other thread out and post it for you to have a read and listen to the vids.

Here you go bud have a listen and let me know if yours is the same.

https://www.scoobynet.com/scoobynet-...l#post11572551

Sub-Subaru

I got all excited as I thought that could be the problem. However, I have listened to the video and that sound (as you guys say) is like a reversing permanent noise.


Mine is a standard WRX box and clutch and it sounds like a scratching noise, like a knife and folk on a plate sound. It is also not permanent in the sense that it is like a pad rubbing on a disc in one spot.


The noise also does not go away when I put the clutch in or the brakes on. I hear it right up until I fully stop at traffic lights, at which point there is no other sound and it is really loud.

mikescooby

iTrader: (2)

My gearbox very faintly makes that sound and can hear it with the radio off. Cant remember wether it still does it or not when i clutch it. I know the noise goes when Accelerating. Years ago on a farm i was on we had a subaru pick up truck and the noise was noticeable on the gearbox and was noisey when takeing your foot of the accelerator. Thats what reminds me of that little faint sound mine makes

ScottyPPP

Mine does that, only started since fitting the pink box clutch.

ditchmyster

iTrader: (7)

That's a reasonable amount of miles to have done on the same oil, I'd be wanting some fresh oil in there if it were mine.

mikescooby

iTrader: (2)

How often should a gearbox and diff oil be changed. Last oil change on my gearbox show iron Filings

ScottyPPP

Every 30k I think.