I came across some videos where people were not able to get their Subaru to pass the 2-wheel climb test, in spite of Subaru promotional videos successfully showing the same thing. I decided to try it myself since I had a Subaru and 2 ramps. There is a ramp on the front left wheel and the back right wheel. This is a real test of an AWD system since we lift 2 wheels off the ground and see if the system can transfer power to the remaining 2 wheels to push the car up the ramps.
The successful result is pretty good for an AWD car without locking axles like a 4×4 off-roader. This is a bone stock 2011 Tribeca and there are more than 60k miles on the original, balding tires.
I mention the limited slip rear differential, but upon review of the video it looks like the VDC is also working here. You can see power delivered to the front left tire in climbing the ramp, even though the front right and rear left tires are spinning. This is happening even though there is no limited slip differential on the front.