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Okay so I have done ALOT of research, let me explain what I have found.
I have a Canadian spec 2015 Evo X GSR if it makes a difference:
Based on my research the Evo X has an LSD front diff, and an open diff in the rear that can essentially lock up or send power to either side through the AYC's torque vectoring.
Also, on an LSD, when you have the car in the air and spin one tire, the other tire should spin the same direction at the same speed always. On an open diff the other wheel would spin in the opposite direction.
So, the other day I was doing an oil change (using AMSOil 5w30 of course) and figured i'd give it a try. I was shocked to find out, that if the info I stated above is correct, that my front diff is OPEN and my rear diff is an LSD!
Is this TRUE?! That is 100% opposite of what the forums have taught me and what I believed for the last 5 years. Did I mix it up, do LSD's spin opposite and Open spin together??? The cars drivertrain is 100% stock and it has only 45,000 km on it so there is nothing broken. Do Evo X's in different countries get different drivetrains? I can confirm I still have AYC for sure, its not an undercover Evo X RS. Thanks for your help guys!

Car details just for fun, 360 bhp apx and 3200lbs weight. Lots of weight reduction and have a 3" turboback exhaust and AEM intake on the stock tune and it runs beyond healthy and pulls strong for a daily reliable rally machine!
 

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Front diff is an LSD, center diff is open, and the rear diff is a planetary LSD with the AYC handling torque vectoring. The system is quite complex in how it works.

If you put the car in the air and turn the rear wheel, either one, all 4 wheels should turn, as those are "driven" wheels.

The center diff (located in the transmission) will always send power to the front wheels "before" the rear, when the ACD is not actuated, because it is mechanically "open". The way it functions is quite clever. Power goes through the final drive gearset, and into the center diff. Internally, on each side, you have spider gears, who's output is separated via two splined outputs. The larger output drives the "rear diff" and the inner spline output drives the front diff. The power that is transferred is sent to the ACD clutch packs. The ACD clutches in the transfer case delineate the power transfer between the front and rear wheels via the clutch packs on the passenger side of the transfer case. So, under normal conditions, the ACD will always attempt to create 50:50 split. But in conditions where that can be detrimental, it "opens" one side of the clutch pack to allow wheels to spin at different speeds, such as in a turn. This is where the tarmac-gravel-snow modes come in. They determine the amount of lock you have via ACD before it unlocks to allow unequal power distribution. So, when the car is off, these clutches aren't being activated, hence why you don't get the wheel turns as expected, because the front and rears are mechanically uncoupled for the most part up front, and energy will pass through the path of least resistance. This is also do in part to the front LSD design, being 1 way. The reason why the rear wheels will turn all 4, is because they are a driven wheel, and by turning them, you force the locking front diff to turn with them, as it is being driven through power transfer through the center diff.

Confusing, I know, but rest assured, there is nothing wrong with your car. If you had a mechanical LSD for a center diff, as in the non ACD vehicles, then I would venture to guess all 4 wheels would turn no matter which wheel you spin, as it is activating the power distribution characteristics of the now mechanically driven center LSD.

Also, to further note. The AYC in the rear doesn't "just send power" to one side of the diff. What it is doing, is detecting the wheel that needs to spin faster (key word here, outside wheel in most every case) and, through mechanical gearing ratios, quite literally "over-speeding" that wheel, meaning the output mechanically spins faster than the input on that particular wheel as compared to the other side. This works in conjunction with the S-AWC computer, which is calculating speed, g force, and steering angle, among other things, to help get you through the turn. Quite literally, that wheel is helping by being mechanically driven faster than the inside rear wheel, which in turn helps push that corner around the turn. A standard 1.5 or 2-way limited slip would "assume" based on wheel speed, that the inside wheel has more traction since it is spinning faster than the outside wheel in a turn. This is also why the front diff is not a 2 way, so that when the power is off, it transfers less power across the wheels and allows the outside wheel to spin faster without locking the inner wheel, which traditionally would cause "push"
 

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Front diff is an LSD, center diff is open, and the rear diff is a planetary LSD with the AYC handling torque vectoring. The system is quite complex in how it works.

If you put the car in the air and turn the rear wheel, either one, all 4 wheels should turn, as those are "driven" wheels.

The center diff (located in the transmission) will always send power to the front wheels "before" the rear, when the ACD is not actuated, because it is mechanically "open". The way it functions is quite clever. Power goes through the final drive gearset, and into the center diff. Internally, on each side, you have spider gears, who's output is separated via two splined outputs. The larger output drives the "rear diff" and the inner spline output drives the front diff. The power that is transferred is sent to the ACD clutch packs. The ACD clutches in the transfer case delineate the power transfer between the front and rear wheels via the clutch packs on the passenger side of the transfer case. So, under normal conditions, the ACD will always attempt to create 50:50 split. But in conditions where that can be detrimental, it "opens" one side of the clutch pack to allow wheels to spin at different speeds, such as in a turn. This is where the tarmac-gravel-snow modes come in. They determine the amount of lock you have via ACD before it unlocks to allow unequal power distribution. So, when the car is off, these clutches aren't being activated, hence why you don't get the wheel turns as expected, because the front and rears are mechanically uncoupled for the most part up front, and energy will pass through the path of least resistance. This is also do in part to the front LSD design, being 1 way. The reason why the rear wheels will turn all 4, is because they are a driven wheel, and by turning them, you force the locking front diff to turn with them, as it is being driven through power transfer through the center diff.

Confusing, I know, but rest assured, there is nothing wrong with your car. If you had a mechanical LSD for a center diff, as in the non ACD vehicles, then I would venture to guess all 4 wheels would turn no matter which wheel you spin, as it is activating the power distribution characteristics of the now mechanically driven center LSD.

Also, to further note. The AYC in the rear doesn't "just send power" to one side of the diff. What it is doing, is detecting the wheel that needs to spin faster (key word here, outside wheel in most every case) and, through mechanical gearing ratios, quite literally "over-speeding" that wheel, meaning the output mechanically spins faster than the input on that particular wheel as compared to the other side. This works in conjunction with the S-AWC computer, which is calculating speed, g force, and steering angle, among other things, to help get you through the turn. Quite literally, that wheel is helping by being mechanically driven faster than the inside rear wheel, which in turn helps push that corner around the turn. A standard 1.5 or 2-way limited slip would "assume" based on wheel speed, that the inside wheel has more traction since it is spinning faster than the outside wheel in a turn. This is also why the front diff is not a 2 way, so that when the power is off, it transfers less power across the wheels and allows the outside wheel to spin faster without locking the inner wheel, which traditionally would cause "push"
This should say "slower"
 
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