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Testing for LSD in AWD?
Posted: Sat Feb 28, 2009 5:21 pm
by SuBaRiNo
I know how to test for an LSD in the older non-AWD subies but does the same apply for AWDs (specifically 01 forester GT)?
It has no sticker on the Diff at all... so if i jack up the back of the car and turn one of the rear wheels and the other turns the same way it's an LSD? If it turns in the opposite direction its an open Diff? Is this right?
I wasn't sure if the AWD gear box interfeared with testing this like this.
I made an assumption that all Forester GTs came out with LSDs but i could be wrong so i want to test it.
Dave
Posted: Sat Feb 28, 2009 5:38 pm
by AndrewT
I think u are right with your thinking on which way the wheels should spin. But ultimately you could take a few minutes and whip the plate off and take a look. Would cost you some gasket goo...
Posted: Sat Feb 28, 2009 7:19 pm
by SuBaRiNo
Prefer to not have to take it appart at all and prefer it to cost me absolutely nothing just for peace of mind. It would be silly to re-use the old oil i remove to take the cover off so that would cost me money especially if i need LSD special oil.
Can someone confirm my method of testing is the same on an AWD vehicle without having to remove anything?
Dave
Posted: Sat Feb 28, 2009 7:40 pm
by Gannon
If it is a forester LSD, chances are its the viscous type, which means that its practically an open diff untill you spin one wheel enough to heat up the fluid inside and tighten the coupling.
Im not sure how you would test it, other than take it for a spin in a wet, grassy paddock and watch both back wheels
Posted: Sat Feb 28, 2009 7:51 pm
by BrennyV
all sf5 forry gt's have lsd's
Posted: Sat Feb 28, 2009 8:29 pm
by AlpineRaven
All this time I've been thru the wreckers I've been looking for LSD as well, once I found an LSD diff but it was clutch pack one both rear wheels turned the same time, not opposite like what open diff would do.. but when i fitted VLSD in my previous liberty, the LSD was worn out but you could turn it around both at the same time..... I might be wrong tho but it was 2-3 yrs ago. I'm still trying to hunt down clutch pack LSD.
yes if it was being driven you would be able to know on wet grass after a couple of donuts.
Cheers
AP
Posted: Sat Feb 28, 2009 8:49 pm
by El_Freddo
AlpineRaven wrote:I'm still trying to hunt down clutch pack LSD.
You and every other subaru nut getting around the yards over here! That explains why you're frequenting the yards more than anyone...
Subarino, the method you spoke of is the only one I know of - the viscous type messes me up so I really don't know here. One way would be hang some circle work then jack up the rear before it gets to cool down

Thoughts anyway...
Cheers
Bennie
Posted: Sat Feb 28, 2009 9:02 pm
by AlpineRaven
El_Freddo wrote:You and every other subaru nut getting around the yards over here! That explains why you're frequenting the yards more than anyone...
Thats damn correct.... wish wreckers apart from Jollys have online pages so you can view them instead of going to the yard.
Cheers
AP
Posted: Sun Mar 01, 2009 1:15 am
by AndrewT
Yer I just figured it would be the easiest way to find out for certain. 5 minute job with you being the seasoned Subaru mechanic you are, and you probably have gasket goo already anyway. Rather than lots of posts of people saying yes this model does, maybe this other model does, perhaps it's lsd, not really sure, chances are this, chances are that, etc etc.
Obviously the best time to do it would be when it's due to have the oil changed, I didn't think of that, but I guess you might still have it under some kind of service warranty

Posted: Sun Mar 01, 2009 1:07 pm
by SuBaRiNo
You have a good point Andrew. Might simply ask Subaru to check it when it goes in for it's next service. Was just hoping it was more common knowledge amoungst AWD subaru owners but it seams no one really knows for sure.
Dave
Posted: Tue Mar 03, 2009 7:24 pm
by PeeJay
My RX has a viscus LSD from a WRX, if you jack just one wheel of the ground and try and turn it it is reasonably hard to do so, not as much as a clutch pack though.
Posted: Tue Mar 03, 2009 11:28 pm
by SuBaRiNo
Is your RX AWD? And if so on a non-LSD diff with AWD, might it also feel like that?
Dave
Posted: Tue Mar 03, 2009 11:47 pm
by Matatak
if you jack all 4 up and in nuetral spin a rear.
If its an Open diff i belive it will simply spin the opposite wheel the other way quite easily
Posted: Wed Mar 04, 2009 6:18 am
by AlpineRaven
SuBaRiNo wrote:Is your RX AWD? And if so on a non-LSD diff with AWD, might it also feel like that?
Dave
All RX liberty are AWD, they dont normally come with LSD.
Cheers
AP
Posted: Wed Mar 04, 2009 7:31 am
by daza
If your Forrie has LSD it's viscous and a vlsd will act like an open diff at hand turned speeds.
It's donuts or open it.
Daza.
p.s The vlsd doesn't use lsd oil, it's sealed so just diff oil.
Posted: Wed Mar 04, 2009 8:20 am
by PeeJay
RX Turbo - It's got a Forrester AWD box and viscus rear LSD. The centre diff is so stiff I can hardly even turn it with a breaker bar. The rear diff is stiff even when cold, if it was an open diff there would be something seriously jammed up. I did have another VLSD here that acted like an open diff, but I suspected it was broken/worn so I didn't use it.
Posted: Wed Mar 04, 2009 10:11 am
by Alex
i can jack up my liberty and see what happens. As i know for sure it has an open diff.
alex
Posted: Wed Mar 04, 2009 10:37 am
by vincentvega
AlpineRaven wrote:All RX liberty are AWD, they dont normally come with LSD.
Cheers
AP
seriously mate. think before post
my open diff one wheel went backwards when you turned the other forwards. All open diffs should do this.
with my VLSD they spin the same way... but thinking about that I am not sure if the tailshaft was turning or not whne I did that
Posted: Wed Mar 04, 2009 1:23 pm
by BrennyV
brennyv wrote:all sf5 forry gt's have lsd's
all gt forrys!
Posted: Wed Mar 04, 2009 11:26 pm
by Matatak
vincentvega wrote:
with my VLSD they spin the same way... but thinking about that I am not sure if the tailshaft was turning or not whne I did that
You've got some problems if it wasnt turning.
All LSD's are pretty shit in an offroader. raise one wheel and literally most of your drive is going to go that way, and we all know subarus raise wheels far easier than alot of other cars.