http://www.cars101.com/subaru/outback/outback2003.html

nipper

 

Yes, you have a rear LSD.

 

And it is probably as useless as the supposed limited-slip in my ******.

No test shows in the least there is any limited-slip action goin' on back there, so it must be burned out well-and-good.


Daqve

 

... other than turning the wheels and flooring it and the rear slides out side ways because both wheels are turning, the rear gets side ways really easy in the snow thats for sure

Well that test won't really tell you much of anything. With enough power or slippery conditions even an open diff will get sideways. The easiest for sure test is to raise both back wheels off the ground, place the transmission in neutral and turn one of the back wheels. If both wheels turn in the same direction you have a limited slip, if they turn in opposite directions you have an open diff.

 

Re: Re: do i have limeted slip rear diff ?

Well that test won't really tell you much of anything. With enough power or slippery conditions even an open diff will get sideways. The easiest for sure test is to raise both back wheels off the ground, place the transmission in neutral and turn one of the back wheels. If both wheels turn in the same direction you have a limited slip, if they turn in opposite directions you have an open diff.

That doesnt really work with viscous couplings. Viscous couplings have to see a speed differnce in the two wheels to work, as opposed to the old mechanical LSD's where they need a diffence in wheel forces to disengage, then that test works.

 

well jacking the car up all four wheels will spin, they better and they do, ive done that before,
and nipper gave me a specs link, and as far as i can tell from the specs only the h-4 of that year and the h-6/v.d.c have the limetd slip rear diff i have a non v.d.c h6
all 4 of my wheels will spin with enough rpms, and on ice.
as soon as i get into a little snow two or three will spin
one in front and two or one in back but that is at full power and by the way it has alot of power
i think alot of the complaints form the h-6 haveing low power is from not letting the rpms get past 4,600 or starting off in
i really like the awd system on my car i have always liked the subaru,
just was wondering is i had a rear lsd , looks like i dont

Tony
this is what i do my serious off roading in

 

this is what i do my serious off roading in

 

Here is a quick run down on which Subies have a rear LSD.

1996-1999: No Rear LSD offered
2000-2002: Rear LSD standard on cars with Cold Weather Package
2003-Current: All cars have Rear LSD except 2007-2008 2.5 Basic, and 2009 2.5i

 

I have a 2002 OBW H6 w/ VDC and I guess cold weather package since it has heated everything.

I'm wondering if it has VLSD rear and it seems most folks would repeat that sentiment. I read through cars101 and there was one page that seemed to suggest the H6 did not, though the standard features said "all outbacks".

 

Here is a quick run down on which Subies have a rear LSD.

1996-1999: No Rear LSD offered
2000-2002: Rear LSD standard on cars with Cold Weather Package
2003-Current: All cars have Rear LSD except 2007-2008 2.5 Basic, and 2009 2.5i

I know the previous owners of my car were pretty gentle with it, I'm trying to figure out how they burned out my LSD so completely. There have been a few times it would have been nice to have it working.


Dave

 

I know the previous owners of my car were pretty gentle with it, I'm trying to figure out how they burned out my LSD so completely. There have been a few times it would have been nice to have it working.


Dave

Well, these VLSDs are very finnicky. If the silicone fluid in the diff overheats, even once, its toast, and it loses most of its ability to transfer torque. Its very easy to overheat the fluid if you don't know what you are doing. If you drive with the spare donut on the rear for more than a few miles, or spend too long trying to get yourself unstuck, that could do it.

Once that silicone fluid has overheated, there really isn't anyway to replace it. The VLSD is a sealed unit, and I don't believe it is possible to replace that fluid.

 

ok heres how my rear diff works,
both rear tires will pull untill it feels one slip then it trnsfers all the power to the wheel that dosnt slip or slip as much if im in the mud and the right tire slips the left tire takes over and back and fouth untill they have equal force to make them both pull, if im at an angle where one tire in the back is off the ground and the other tire is in the mud and the one in the mud will turn ,or spin
the front does the same thing
when im on a trail and i go over a hill at an angle the tires that are off the ground will not slip only the tires that are on the ground ,will slip or produce power
now i put it in a situation that i know i will have to back out of so that i can see the wheels actually spin,
none of my other off road truck with out lockers or trutracs did this wich ever tire was off the ground it would slip
i have a video clip and pics of the vehicle on an aproache to a crest that i know it will not make it over and the one wheel in front and one wheel in back is off the ground, ( opposite sides) they will not spin only the ons that are on the ground do,
i only do this for a few seconds as to not burn up anything
now with my off road experience that is lsd both front and rear

Tony

 

ok heres how my rear diff works,
both rear tires will pull untill it feels one slip then it trnsfers all the power to the wheel that dosnt slip or slip as much if im in the mud and the right tire slips the left tire takes over and back and fouth untill they have equal force to make them both pull, if im at an angle where one tire in the back is off the ground and the other tire is in the mud and the one in the mud will turn ,or spin
the front does the same thing
when im on a trail and i go over a hill at an angle the tires that are off the ground will not slip only the tires that are on the ground ,will slip or produce power
now i put it in a situation that i know i will have to back out of so that i can see the wheels actually spin,
none of my other off road truck with out lockers or trutracs did this wich ever tire was off the ground it would slip
i have a video clip and pics of the vehicle on an aproache to a crest that i know it will not make it over and the one wheel in front and one wheel in back is off the ground, ( opposite sides) they will not spin only the ons that are on the ground do,
i only do this for a few seconds as to not burn up anything
now with my off road experience that is lsd both front and rear

Tony

Well, I can guarantee you don't have an LSD in the front, Subaru has never put a front LSD in any Outback. Are you sure you don't have VDC? Because it can force the car to do what you are describing by applying brakes to the wheel that has lost traction, and transfer the power to the other wheel that way.

As for the a rear LSD, it won't transfer power back and forth, it will just psuedo-lock up the rear end so that power is split 50/50, but it doesn't do this very efficiently.

 

yeah i didnt think subaru made a front lsd for that model
and no i deffinetly do not have a vdc model
thats just how the awd is working on my vehicle
i tested it in many diff anfles and variations
and it does exactly what i said in my last post
maybe something is wrong with my awd and if there is i like what it is doing and dont want to fix it, i dont have alot of excperience with the subarus ive only owned 3
03 h-6 o.b. current
96 legacey wagon a/t retired it in feb 09 with 390,000 miles
78DL front wheel drive 5 speed ( back in highschool) left it to my freinds when i went to the army i heard it went a few more years before the clutch went
i beat that car up bad before i gave it to them and it was very fast and durable
fast for back then any way i had it in from 1984-1987

thanx for all the help and explanations
maybe ill get the dideo clip of the car on yuotube so you can see the wheels spin like a 1/4 turn then switch sieds to find more grip back and fourth till it gets through the slipperystuff, and one with two wheels off the ground one front one rear opposite sides, the ones on the ground ( in slippery mud ) are turning and the ones in the air do not turn
i turned the car around and did the same thing with the other side and it put the power to the wheels on the ground
there was one or two times that the rear spun both tires for a moment

thanx
tony

 

Juan, in post #5 described a way to tell, by raising the rear of the car. It doesn't confirm if the the viscose coupling is working when one wheel spins, but will indicate if the differential has the coupling built in.

This works because the viscose coupling is supposed to be sealed between the left side gear and the differential housing by rubber seals, in order to prevent mixing of the special silicone oil in the coupling with the gear oil in the rest of the differential. The seals are quite tight -- they can be because for most normal driving, the left side gear and the differential housing turn together, so there isn't a lot of wear. When one wheel loses traction, there will be slippage at the seal surfaces, but only for the time of the slippage. So the seals can last a long time if not abused.

Because the seals are fairly robust and tight, the side gear and differential case are sort of held together by the seal friction. Consequently, when the rear wheels are raised and the transmission is in neutral, turning one rear wheel causes the other wheel to turn in the same direction. (The drive shaft also turns, of course, because the differential case with the crown gear is turning). Similarly, if the drive shaft is held in place (e.g. MT in gear), it will be more difficult to turn one rear wheel (you're fighting the seals) and to the extent it can be turned, the other wheel will turn in the opposite direction. But the drag will be very (!) noticeable.

In a non-LSD differential, when turning one wheel the other turns in the opposite direction and the drive shaft for the most part, doesn't turn, or turns slowly relative to the wheels. (This depends on drag in the opposite wheel. If the brake is binding, the wheel will turn less, and the drive shaft more.) Turning the first wheel is easy provided the brakes are off. Also, if the drive shaft is prevented from turning, it's still easy to spin one wheel while the other turns in the opposite direction. Not so with a viscose coupled LSD.

Again, this can confirm whether or not the differential has a viscose coupling, but it does not confirm if it is actually functioning (i.e. the special fluid becomes more viscose when there is wheel slippage). Also, if the seals happen to be badly worn, the friction might not be as noticeable; but if this is the case, there's a good chance the silicone liquid has already mixed with the gear oil and the coupling isn't working in any case.

 

Mine is so wiped it acts completely as though there is no limited slip.

Dave

 

interesting cars101 does suggest it has limited slip. last time i had both rear wheels off the ground i spun one side and the other side spun the opposite direction. i'll check again.