pin one tire the opposite spins in the same direction.
folks that do a lot of Subaru's are suggesting that these VLSD units don't last very long, they essentially fail to an "open" or non-LSD diff. so like he said, even if it's passing that test as an LSD it might not mean it's really gaining you any traction.it only verifies the probable existence of a LS differential; it does not verify if the LS viscous coupling will actually work properly when one wheel loses traction.
The viscous couplers inside the two different differentials are pretty much the same mechanically, at least according to the service manual diagrams. But their locations could be the distinguishing factor.are the designs so different that fail in opposite directions?? did the engineers plan on these failing in different directions?
Ah, binding on turns. With a Subaru automatic transmission this could be due to the multi-plate AWD transfer clutch remaining engaged when it should be at least partially released.That's why I'm asking because I'm afraid mine might be the cause of the binding I'm experiencing when I turn. I had one wheel on the ground and the other I was able to turn so I guess it isn't stuck locked. I am interested in finding out a way to test it out though to be sure.
Why would engineers want to have, say, 25% transfer? In both cases, the objective is to have both outputs (front and rear drives, or left and right axles) turning at the same speed.The rear can (I'm supposing) transfer somewhat linearly from 1% on up.
you have torque bind, you can ignore the rear differntial for assessing this issue.That's why I'm asking because I'm afraid mine might be the cause of the binding I'm experiencing when I turn.
Yeah, every drawing I've seen shows the viscous units drawn basically the same way, internally, so, I'm unclear as to why there's the word 'locking' used for soob MT center diffs.Why would engineers want to have, say, 25% transfer? In both cases, the objective is to have both outputs (front and rear drives, or left and right axles) turning at the same speed.
In the case of the rear differential, if one wheel has good traction, and the other not, the VC action slows the spinning side. By doing this, torque is built up in the drive train and therefore the wheel with traction is able to move the car.
When as a result of the VC action, the wheel without traction is no longer able to spin faster than the one with traction, it can be said that the VC is "locked", but in fact the VC fluid is just maintaining enough friction between the plates of the coupler to prevent the wheel with less traction from breaking away. It's a dynamic process.
The same applies to the center differential's VC.
A VC can "lock", but this is more often due to shifting of the plates such that they come in physical contact. This is not an intended situation, but can happen under extreme conditions.
There's descriptions of the center VC and the rear differential VC action in the "Mechanism and Function" section of the factory service manual, I believe beginning with 2002 editions, or thereabouts.
I would look at the context; that is, where the word "locking" is used.. . .very drawing I've seen shows the viscous units drawn basically the same way, internally, so, I'm unclear as to why there's the word 'locking' used . . .
some folks experience noise/jerkiness from bad driveshaft components. I suppose that cpuld also feel like it's from the rear of the car.The only reason we suspect the diff is because the noise is comming from the rear of the car instead of the center as far as we can tell.
Perhaps some more detail about the "noise" might help. (I don't see it mentioned earlier.)The only reason we suspect the diff is because the noise is comming from the rear of the car instead of the center as far as we can tell.