The AUSubaru.com.au Forums

Hey folks.

I have a 1999 Outback, and for a while now it has been making odd noises. Almost like the noise you get when you put a card on the forks of a bike, and ride it around (like kids do) - but fainter. It started ages ago, but I couldn't find where it came from and didn't seem too bad. Ended up driving across the country with it, and it was fine. Until a few weeks ago when I reversed out of a parking spot at work, and the whole car clunked and shook - I thought I'd run over a brick or something. I drove home, and the car didn't seem unhappy or anything. But the next day I went to the shops and it did the same thing again - this time in reverse, and then again a couple of times in first. It was fine once I got going, and was fine at the shop carpark, but driving home this noise became very loud. Since then I haven't driven the car except to try and listen for where it is coming from. It's not as loud now as that one day, but I'm still not willing to risk driving to work with it.


The noise doesn't change with engine revs, it doesn't change with the gear selection (and hasn't clunked like that since that day), and coasting out of gear/with the clutch in doesn't change the noise - except with car speed. It tends to get louder when I'm decelerating, and fainter when I'm accelerating, and changes pitch with the speed.


According to the workshop manual's FIM it is probably a diff - it sounds more like the front than anything - but I'm not 100% sure.

I haven't been able to find anyone who will sell me a front diff by itself (in Perth), but I have a wrecker with a Forrester gearbox for $1550. It was that, or over $4000 to get a mechanic to do it.


So. My questions are: Does that sound like it's a diff? Or something else, perhaps. And if so does that sound like a decent price for the gearbox (or does anyone know of a place that will sell the diff by itself in Perth?). And, for that matter, is a forrester diff the same as an outback one? (I can't remember the year model of forrester - but the plan was to remove the old one before getting the new one, so they can be compared. This has sort of fallen down due to lack of time, help, and equipment. heh.)


Anyway, thanks folks.

It will just be one of the four front driveshaft CV joints.
If it changes alot when you turn the steering wheel then you can most likely narrow it down to one of the Outer joints.

CV joints are new, put in last january. The sound doesn't change on cornering, either.

I'd be pissed off if it was the CVs! heh.

Not wanting to alarm you but it could be an issue with the centre coupling but without actually hearing it i could not be certain. The plus side of things is, is that if the centre coupling is the problem it can be replaced without removing the gearbox.

Ah! This is the centre diff, or the flexing point halfway down the driveshaft?

The noise is... indistinct. I can't tell 100% that it's coming from the front, but it's more front than back, so... yeah. If it is this, how can you tell? I can't stick my head under the car while I'm moving, unfortunately. hehehe.

Did they replace all 4 front CV joints or just the inners or maybe just the outers?
Maybe something external like an exhaust hanger has broken and the exhaust is rubbing on the tailshaft...I'd get underneath with a good spotlight and go over looking for evidence of rubbing everywhere, ie shiny metal on moving parts...

still could be wheel bearings too...my gen3 shat a wheel bearing, and your description sounds pretty similar to what was going on with mine..

alex

aie. So many things... heh.

I spent a few hours under there on saturday, there was no evidence of rubbing that I could see, though. We managed to get the driveshaft out, and exaust and heatshield before we got the ****s and gave up (most of the bolts were crazy tight - I've got some penetrant oil from work and I'll slosh that around the culprits so I can have another go tomorrow arvo after it's soaked in. I'll have a good long look at the driveshaft, and the other bits I can see now tonight, maybe something is evident.

I suppose while I have it off the ground I can have a look at the bearings, too. The sound is fairly central, though.

As for the CVs, I changed both front driveshafts - so inner and outer on both sides. The boots are still intact, and this sound is different to CV clickiness.

Damn mechanical bits. Give me wires any day! heh.

(Thanks for all the advice, too, guys!)

Alex wasnt one of ur Castle nuts loose that can do it.

id say check ur castle nuts THALASS if not done up tight enough (can be found out by wiggling the wheel up and down in the air.) then it allows the hub to move around and clock and crap liek that.

but if its central then Centre COupling thingo Subi Wan mentioned maybe?
hes ont he money most of the times.

A cause of the centre coupling falure is generally hard frequent take offs. This causes excessive load on the Large circlip that holds it all together, i havent seen a car lock up because of this failing but it does give a nice clunk when forward and reverse direction is changed.

It would be very unusual if it was to be a problem with the front diff as the bearings rarely wear out.

It could also be something to with the centre tailshaft bearing but unles you have had it imersed in water for long periods that is also doubtful.

A front wheel bearing will generally start to groan as it dies a hard death but then all of a sudden the wheel will take on its own life, that applies fron or rear.

I do feel that unless the car has a heap of Ks on it then you are looking at the centre diff but if it has high ks or an abusive life then you could be looking at a crack in the centre bearing in the gearbox. If it is that bearing you will loose a gear every now and then and it will get a noisey whirr happening.

OK... So by "centre diff" you mean "centre coupling"? The flexible joint halfway down the driveshaft to the rear end?

If so, what are the symptoms? I've turned it by hand, and there is a distinct clunk once per revolution, but it was still hooked up to the gearbox at the time. Should the joint have any fowards-backwards play in it? It moves quite easily in that direction.

The car has 170996km on the clock, and I must confess I do tend to takeoff a bit quicker than I should (or, at least, try to - she's no WRX). I hope it is this coupling, as it's already (loosely) disconnected.

How would you test it when it is removed from the vehicle? It's only six loose bolts holding it in right now.

Yeah centre coupling = centre diff. You have turned the tailshaft or the outlet shafti n the gearbox, to listen and fell for a gearbox noise you will have to isolate it. The clunk could be the coupling or a support bearing.

Well... I got my car back together... hah.

Managed to get it partially dissassembled (driveshaft, exaust, a few things off of the gearbox up top) with my cousin before his hangover became unbearable and our enthusiasm waned... Mostly because most of the bolts were on way too tight and I don't have an air gun. (even with a breaker bar and extension they wouldn't come off!)


Trouble is that I don't have most of the equipment (or metric tools) I need. Hell, I'm not even sure we'd have been able to drop the gearbox out with the car jacked up as far as it was - and I couldn't get it any further.


So... Anyone know of a decent workshop in Perth that isn't too expensive and knows what they're doing with Subarus? I was originally quoted over four grand - which is why I decided to have a crack myself. What I need is my own house so I can have a decent set of metric tools and equipment and such in the garage. All my tools are imperial. I'm pretty sure I lose engineer points or something for lacking the proper tooling. :P

I'm up in Ellenbrook. Wangara isn't too far, the place I was going to buy the new gearbox from is in Wangara. Damnit, where'd I put that sheet of paper with names and prices...

All fixed now, thanks to Paul's RSR! Woot!

Did you find out the issue?