Failed VCU (or is it VCD...)?

[Sytech]

I have what has been diagnosed as a failing (Failed) Viscous center diff assembly and need to source a replacement.
The offending unit Currently resides in a 1999 Forester Ltd.
Any assistance on locating a replacement would be appreciated just about fell over when I priced a new one:(
Thanks

[Outback bloke]

http://www.sunspares.com.au

Tell them "The bakcyard boys" - us here - sent you.

[AlpineRaven]

how did the centre diff fail?
How did you find out/what was the foz doing (ie. Still driveble or not moving etc)?
Cheers
AP

[FROG]

They generally fail due to uneven tyre sizes

[Porty]

Hey mate i have just been through the same thing, but with an 02 impreza. Yeah $1450 from subaru was scary at first so i took a gamble n got one secondhand for $150... It ended up being screwed too.. I also got onto a certain company on the net and they said they would sell me one for $900, but it didn't come with a warranty.... So i bit the bullet and crawled back to subaru... 20k and 1 year warranty was better than none... I photographed every step when i changed it too...

ya never know but, you could find a good cheap second hand one and it may last you for 5 years or whatever... Or even a brand new one for cheaper and it may turn out alright..

Anyways good luck, hope you end up better off....

[RX Coupe]

I had the same problem with my 02 Outback in Ballarat earlier this year. It cost me just under $1600 to get it fixed by Subaru.

JC

[AlpineRaven]

I had the same problem with my 02 Outback in Ballarat earlier this year. It cost me just under $1600 to get it fixed by Subaru.

JC

Hey mate i have just been through the same thing, but with an 02 impreza. Yeah $1450 from subaru was scary at first so i took a gamble n got one secondhand for $150... It ended up being screwed too.. I also got onto a certain company on the net and they said they would sell me one for $900, but it didn't come with a warranty.... So i bit the bullet and crawled back to subaru... 20k and 1 year warranty was better than none... I photographed every step when i changed it too...

ya never know but, you could find a good cheap second hand one and it may last you for 5 years or whatever... Or even a brand new one for cheaper and it may turn out alright..

Anyways good luck, hope you end up better off....

I have what has been diagnosed as a failing (Failed) Viscous center diff assembly and need to source a replacement.
The offending unit Currently resides in a 1999 Forester Ltd.
Any assistance on locating a replacement would be appreciated just about fell over when I priced a new one:(
Thanks

What was the symptoms of blown centre diff? (just wanna hear your stories..)
Cheers
AP

[RX Coupe]

Mine was I left Adelaide fine int he early hours of the morning driving almost non stop to Ballarat. When I got there I turned a few sharp corners and it felt like I had a welded rear diff as the back end started to hop around corners and shudder a bit. Took it straight to Subaru and they able to fix it the next day and drove us around where we wanted to go in a brand new Impreza. I then done another 4500km around NSW straight after it was fixed with no other problems showing up. The car never gets driven hard but does lots of highway or city driving. Most km's done quicly in it was 5500km in 9 days all highway and dirt roads.

Cheers,
JC

[AlpineRaven]

Mine was I left Adelaide fine int he early hours of the morning driving almost non stop to Ballarat. When I got there I turned a few sharp corners and it felt like I had a welded rear diff as the back end started to hop around corners and shudder a bit. Took it straight to Subaru and they able to fix it the next day and drove us around where we wanted to go in a brand new Impreza. I then done another 4500km around NSW straight after it was fixed with no other problems showing up. The car never gets driven hard but does lots of highway or city driving. Most km's done quicly in it was 5500km in 9 days all highway and dirt roads.

Cheers,
JC

Interesting.... I've heard different stories about failed centre diff.
Cheers
AP

[Tone]

G'day Everyone,

I am interested to know more about this. I have just bought a 93 Liberty Automatic. I test drove in the dry on sealed roads everything seemed OK. I took delivery of it today in the rain. Noticed at the first corner that the rear wheels aren't doing anything!

I am wondering what else I should check prior to changing out the Centre Diff? From the few threads I have taken a look at it sounds like there is a control unit, disengage solenoid and other components as part of the system are these prove to problems and what tests should I do?

If I do need to change out what is required? Can it be done with the gearbox in the car or does the it need to be removed? Any ideas on time to change out or any tips/tricks would be much appreciated too.

Thanks,

Tony

[AlpineRaven]

G'day Everyone,

I am interested to know more about this. I have just bought a 93 Liberty Automatic. I test drove in the dry on sealed roads everything seemed OK. I took delivery of it today in the rain. Noticed at the first corner that the rear wheels aren't doing anything!

I am wondering what else I should check prior to changing out the Centre Diff? From the few threads I have taken a look at it sounds like there is a control unit, disengage solenoid and other components as part of the system are these prove to problems and what tests should I do?

If I do need to change out what is required? Can it be done with the gearbox in the car or does the it need to be removed? Any ideas on time to change out or any tips/tricks would be much appreciated too.

Thanks,

Tony

Tony,
Welcome...
The first place i would check is the fuse which is on passenger side, check if it is induct, if not then next step with other things...

You should notice the rears (AWD) working in wet weather, in our recent wet weather i took a corner pretty hard without loosing control and i noticed that AWD was working well.
Cheers
AP

[Tone]

Thanks for that tip. I will check that.

I checked that there was no fuse in the holder that switches to FWD, but didn't think of one in the fuse board.

There is definitely something wrong. The same conditions in my 90 liberty manual or 2000 Outback Auto would have had no noticable wheelspin. Today this car got the front wheels spinning like you would expect from the rear wheels of a Holden ute!

[Tone]

Couldn't help myself, I went out in the dark to take a look. The only fuse I could find is the one that you insert to make the car front wheel drive.

Also found this great article on replacing the centre diff in a forester manual http://www.subaruforester.org/vbulletin ... hem-46979/

Wondering how similar the auto gearbox will be.

Even though I have some troubleshooting to do first. Can anyone recommend a good source of spares?

[vincentvega]

completely different to a manual. there is a wet clutch pack that transfers power to the rear end as required. most of the time they are basically a FWD car.

you are probably stressing about nothing. how does it drive?

[Tone]

Drives just like a front wheel drive

Unfortunately I am an AWD addict and would get very annoyed and frustrated whenever I put my foot down and got wheelspin.

[Gannon]

How do you know the rear wheels arent doing anything?

The thread is also referring to a manual gearbox, which contains a viscous centre limited slip differential

Your car is an auto, which (if its a AWD model) has a multi plate rear transfer clutch.

Normally when it fails, the Duty Solenoid C goes open circuit supplying full fluid pressure to the clutch pack and makes the car behave like a locked 4wd vehicle.

If it is not sending any power to the rear wheels, either the FWD fuse is in (located in the engine bay near the strut tower) or the clutch plates are worn (unlikely)

[Tone]

Thanks Suparoo

In the same conditions I could have put my foot flat to the floor in my 2000 outback auto or '90 Liberty Manual and have no observable wheelspin. When I put this car to the same test it kept freely spinning wheels for about 10 seconds at which point I realised that there was definitely something wrong.

In my 2000 outback I used to notice on wet grass that I could get about half a revolution of the tyres sometimes before I felt it lock up and gain traction from the rear.

The FWD fuse is out. I am wondering if there is any way that the fluid pressure could be low. Does the solenoid ever get stuck shut? Are there any filters or possibility of blockage in the solenoid or elsewhere.

The auto gearbox seems to be behaving well. I am wondering if I should do an oil change to ensure correct quality and grade.

The 2000 outback had 256000km's on it when a guy t-boned it and it was working fine. Is it still possible that the plates may be worn at 217,000kms if the car has been driven hard or abused?

[Tone]

OK, I have just had this confirmed by a Subaru dismantler / mechanic. It definitely has no traction to the rear, something he has never seen happen to one of these. He suspects that it is an internal problem with the gearbox and that the most economical fix is replace with a 2nd hand automatic gearbox at $800 fitted with new seals, filter and oil.

Does anyone have any other suggestions or recommendations for me?