[Kalud]

Came across that video, thought it's interesting to share...

All wheels drive systems comparison.

Audi Q5
vs
Mercedes GLK
vs
Lexus RX 350
vs
BMW X3

[335_MI6]

nice

[spool twice]

I'll probably get flamed for this...

It's impossible to lose complete traction (yes, even ice has some "traction") in real world driving such as the test on the rollers aside from the tire being completely up in the air. Therefore, these tests on youtube are irrelevant to a prospective buyer who will use this "AWD" system in on-road situations 99% of the time.

Torsen-based Quattro is a mechanical based system which will require driver intervention when the tires are on rollers. If you are curious how the system operates, Wikipedia it and it will explain how Torsen functions and that it needs some resistance for torque transfer, otherwise it acts like an open differential. In a wheels on roller or wheels in air situation, the driver either needs to:

1) step on the brake at the same time to create this resistance within the drivetrain

or

2) use the E-brake and the mechanical Torsen center differential will transfer torque to the rear wheels.

out on a snowy road, I would prefer a Torsen based-Quattro since it's technically an "active" system (even though the center diff isn't electronically controlled) and will divide torque within it's set TBR, whereas other systems that use an electronically controlled center differential (such as a Haldex-based system) are "re-active" which means it'll only actively transfer torque when wheelspin is sensed.

I've had 328Xi for loaners during snowy days when I lived up in South Dakota, you can catch the system dividing engine torque in unnatural feeling ways in snow and ice situations vs. having a smooth transition.

[zipstic]

Edit: Ahhhh! Beat me to it ^^^^^^^^^^

Cool video.

Still wish my 335xi has Audi's Quattro Torsen system though.

[Carl Morris]

Hmmm...I wonder what happens to the BMW if you put rollers under both rears and one front. Is there any side-to-side action in the front?

[DannyZRC]

spool, nothing so complicated necessary as talking about zero traction (ice, btw, is about as zero as those rollers).

they turn the TCS/ESP off on the cars they want to look bad, and leave it on for the car they are promoting.

all modern cars have systems that will brake spinning wheels, the only real differentiator in AWD systems is how elegantly the braking is accomplished, and how much torque capacity there is in the secondary drive system for cars without center diffs.

[mashimarho]

Nice video!

[AWD Addict]

Originally Posted by spool twice

whereas other systems that use an electronically controlled center differential (such as a Haldex-based system) are "re-active" which means it'll only actively transfer torque when wheelspin is sensed.

xDrive also uses yaw and accellerator position in it's determination of power distribution, not just varying degrees of traction.

HItting the DTC button feels pretty much as good as any mechanical system I've driven, including the EVO and Subaru systems.

[freshnezzz]

nice

[avenger2540]

No matter what!!! BMW is the best,thats why we got one...

[turbotoy4me]

Originally Posted by avenger2540

No matter what!!! BMW is the best,thats why we got one...

+1

[spool twice]

Originally Posted by DannyZRC

spool, nothing so complicated necessary as talking about zero traction (ice, btw, is about as zero as those rollers).

they turn the TCS/ESP off on the cars they want to look bad, and leave it on for the car they are promoting.

all modern cars have systems that will brake spinning wheels, the only real differentiator in AWD systems is how elegantly the braking is accomplished, and how much torque capacity there is in the secondary drive system for cars without center diffs.

the main difference between rollers and ice is that if you both any of those vehicles in this test with all four wheels on ice, they will get themselves moving. If you put all four wheels on those rollers, all of the vehicles would get stuck and would require intervention.

The only time you'll have zero traction in "real" world driving is if one or more wheels are off the ground, which will rarely happy unless you're off-roading (in which case you'll want a true 4WD system with locking center, front, and rear differentials anyways), in the ditch, or rolled over up-side-down because of an accident.

[EyeGuy]

Lol if you think x-drive is the best awd system. Especially at the guy who thinks the sti dccd and the evo system even compares.

[335xi Kevo]

Ive had a b7 Audi a4 quattro and it was good in the snow. This year my 335xi e92 seemed to do better, I honestly was astonished. I personally didn't have high hopes for xdrive.

I was able to safely maintain higher rates of speed and not feel "compromised" by the conditions.

[zipstic]

Originally Posted by 335xi Kevo

Ive had a b7 Audi a4 quattro and it was good in the snow. This year my 335xi e92 seemed to do better, I honestly was astonished. I personally didn't have high hopes for xdrive.

I was able to safely maintain higher rates of speed and not feel "compromised" by the conditions.

Interesting. I felt like my B5 Audi A4 Quattro drove better in the snow. Were you running snow tires on both?

[335xi Kevo]

Originally Posted by zipstic

Interesting. I felt like my B5 Audi A4 Quattro drove better in the snow. Were you running snow tires on both?

Both had all seasons on them. Believe me I was shocked.

[jmaville]

Put my VW Touareg V8 with locking diff on those rolls......and see what happens!

I hate to admit this but I was always an Audi guy until I bought my 335xi.....My mom has had 4 different Audi's.....and 4 Different BMW's She goes back and forth...Audi's are better in the snow....however BMW's are much more fun to drive and are still good in the snow.... My Touareg is better than both though ....

[zipstic]

Originally Posted by jmaville

Put my VW Touareg V8 with locking diff on those rolls......and see what happens!

I hate to admit this but I was always an Audi guy until I bought my 335xi.....My mom has had 4 different Audi's.....and 4 Different BMW's She goes back and forth...Audi's are better in the snow....however BMW's are much more fun to drive and are still good in the snow.... My Touareg is better than both though ....

Why do you say that? Ground clearnace?

[jmaville]

Because I have a 05 Touareg with air suspension and locking center and rear diff and its the just better in every way....besides gas mileage! ha

It has many of the same interior features as the VW Phaeton which was a 70-100k new and shares a lot of cayenne parts as well....

The thing is made like a tank.... behind all the panels it has soft moulded foam so there are no rattles with wiring and dampens driving noise..... Not to mention its a 2005 and I haven't had on problem with it.....

[zipstic]

Originally Posted by jmaville

Because I have a 05 Touareg with air suspension and locking center and rear diff and its the just better in every way....besides gas mileage! ha

It has many of the same interior features as the VW Phaeton which was a 70-100k new and shares a lot of cayenne parts as well....

The thing is made like a tank.... behind all the panels it has soft moulded foam so there are no rattles with wiring and dampens driving noise..... Not to mention its a 2005 and I haven't had on problem with it.....

You should try driving an allroad. It has air suspension, torsen diff, can running skinnier tires (which is always a plus in winter) avail in a 6 speed, ESP, incredible 2.7TT motor

[jmaville]

Yeah mom my used to have one...it was nice....but like I said my mom used to have one....that engine is amazing though I'll give you that....