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  #1  
Old 13-06-2009, 11:02 PM
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Default centre diff issues

Just chasing some idea's on what happens to subaru centre diffs when they start to wear out.

When i first got my car, the car was tight feeling, and when parking especially when hot resulted in clunking and banging from the drivetrain. Under hard acceleration the car felt like a AWD car, and felt like front and rear wheels both spun in the wet.

lately i have noticed (in the last 4 months) that it doesnt clunk when parking when hot, and doesnt feel as "tight" to drive as it did before. Now in the wet it almost feels like toomuch power is going to the rear wheels. It still puts power to the front but something feels different, and in all honesty i really prefered it when it was tight feeling.

Now what i want to find out is how long do the centre diff's last before they wear out? what are the symptoms of them wearing out?

with the car up in the air it still feels like if you hold the rear wheels and turn the front that it is tight, but possibly not as tight as before.

I guess also, if it is starting to wearout what are replacement options?

Thanks

Tom
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Old 14-06-2009, 09:00 AM
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more likley the rear diff,
but if you launch, and only the front light up, then its your centre.
subaru's without dccd drive the fronts before rear.
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Old 14-06-2009, 03:12 PM
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well, i have launched her many times, she always spins all 4, but i did snap both front drive shafts earlier this year on a launch. weird thing is the car actully drove ok too, apart from the noise of 2 shafts banging around. The rear diff does work although doesnt feel super strong. mayby that is causing the strange feeling?

I will go for a few launches later this arvo
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Old 15-06-2009, 08:35 AM
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I wore out the plates in my rear diff and then 6 months later the centre diff plates were shagged. The 5 speed DCCD can not be rebuilt. i.e. find a 2nd hand one or buy a fixed sti motorsport one.

Fixing the plates in the rear diff is a cheap exercise.

Brendon
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Old 15-06-2009, 01:20 PM
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Quote:
Originally Posted by urabus
Fixing the plates in the rear diff is a cheap exercise.

Brendon
Assuming it's a plate LSD, which most are not. Viscous LSD is not servicable, neither is a suretrac.
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Old 15-06-2009, 06:22 PM
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i think it is a viscous Rear lsd. Pulled the centre diff out today. the viscous fluid was all black and very smelly. I think i will just get a new one. any options on getting seccond hand?

how strong are the rear diffs meant to feel? with the car in the air idling in 3rd gear, you can hold one of the rear wheels stopped, it still feels like a lsd but im not sure how strong it is now.

what would be a better option a sti 20kg centre (i think that one is stock in the v6's?? or a dccd.
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Old 15-06-2009, 06:35 PM
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your sti would have had a 12kg centre too, a 20kg will certainly add a lot of noise on turns.
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Old 15-06-2009, 06:41 PM
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what other effects will it have on how the car drives? i have been reading that the clunking when turning when hot is a sign of a failing centre diff?

but i can understand a strong centre clunking when turning. how can i identify what sort of diff it is?
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Old 15-06-2009, 06:43 PM
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understeer if your not prepared for it (its like driving a 4wd with the hubs locked on the tarmac)
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Old 15-06-2009, 06:55 PM
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so they bias the car to want to understeer more. what about if you are prepared how do they react?
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