The transverse cars are haldex. I'm just hoping thr Q5/Toureg don't have a similar system.

Never mind you do say ABS will start braking causing some power flow to the other axle. According to BMW & Acura site XDrive & SH-AWD will send most power to wheel(s) with most traction. So is this different in Quattro? BMW says XDrive sends also 60:40 power under normal conditions so that's same distribution as Quattro if true. SH-AWD will send most power to FWD axle as but in cornering it will use torque vectoring to outer wheels. So that system might be more fun and better in cornering unless these systems have that as well...

Lucien E "sending power to the axle with the most traction" is kind of a dubious statement with many systems. xDrive can send 100% of the power to the rear because the rear axle is always connected. The front axle can be connected or disconnected between 0-100%. This means that the most power that can be sent to the front if all wheels have traction is 50%. That "if all wheels have traction" part is important to remember. Also, while the wet plate clutch system in xDrive tends to have a 60/40 power split it is not constant like Quattro. With the Audi system power is always 60/40 unless slip occurs. The xDrive system can and will change the balance from 0/100 to 50/50 any time.

"Better'' is a tricky word. Both systems have pros and cons. SH-AWD includes a torque vectoring rear axle while only some implementations of Quattro include one. Quattro has a permanent rear wheel bias while the SH-AWD system usually displays a front wheel bias although the system will switch to a rear bias whenever the software commands it. Quattro's true center differenntial will make it a little more sure footed at low acceleration starts in snow and ice. IIf I had to pick I think I would probably take the permanent AWD feel of Quattro.

Alex on Autos According to some recent comparisons I saw SH-AWD doing bit better actually in snow and ice. But not sure always if it's apples to apples comparison (especially tires). Alex will you test the TLX AWD and BMW 4 series gran coupe X-Drive? BMW might be more fun to drive on dry roads if it has that RWD bias. Not sure how those AWD systems otherwise compare.

Lucien E I hope to have both in short order but I don't know exactly when. Keep in mind that snow performance often has more to do with tires than AWD systems.

Alex on Autos Thanks looking forward to your reviews:-).

Would it be possible to add a sport differential? Like the s4 has? I head that either the sq7 or the v12 had a torque vectoring differential, but haven't been able to confirm it.

it's a press vehicle

A lot of press vehicles come without obnoxious signs, so that does not prove much.

I only learned of it earlier, from photos the ultra quattro sure looks like a haldex system of sorts. Full time fwd with rear wheel assist if anything.

@@SupramanTRD it is different. Off the standstill, there's traction front and rear - thats the default. It only decouples when it detects no need for rear traction. Also the system is predictive - it does not necessarily wait for front to slip, in order to engage rear. None of the conventional "on demand FWD based AWD" do that, even more so, to achieve 85% power to rear axle... To back up your point... This is not a true old fashion torsen center diff(I, myself would prefer that also). It is a multi plate clutch(in transfer case) that is by default engaged to send power to the rear. I believe another difference between Haldex and this one is the hydraulic system(in Haldex) alternates traction between front/rear(with a 50% max on the rear), vs sending power simultaneously