pamiboy

I have seen a few videos on you tube pitting the Mercedes 4 Matic against other systems such as Quattro, X drive, Lexus, etc and it seems the 4 Matic doesn't match up to them in many situations. I had always thought that these are essentially same systems with different names by different manufacturers. Can someone knowledgable about AWD shed some light in this area. Thanks.

Arrie

Audi Quattro system is the best hands down. They have it perfected way better than anybody else. Audi also was the first one to introduce a true AWD system in the cars.

BenzV12

Assuming you ask W212 4MATIC vs others but I thought I should share some kind of things I read on the cars mag although it was related to A45 AMG and CLA45 AMG 4 MATICs .
Even for MB 4 MATICs seem to work differently depending on what you drive.The test performer dropped a few notes when he test drove A45 AMG and CLA45 AMG . He said either these cars' 4 MATIC systems work different in comparsion with S350 BLUETEC 4 MATIC and these cars are mostly inheriting FWD characteristics unlike other 4 MATICs in MB model line up

pamiboy

Is the AWD system engaged all the time or is it only when needed ? In one of the videos the Mercedes front wheels were put on free rollers but the driver was unable to move the car as there was no power going to rear wheels. Is it possible? I thought these cars were primarily rear wheel drive.

YYZ-E55

Current MB 4MATIC (excluding NGCC models) is RWD bias with open differentials front/center/rear. It is always active, with a variable split depending on the model (30/70 to 50/50 IIRC).

4MATIC uses the wheel speed sensors (4ETS = 4 Wheel Electronic Traction System) to detect traction loss and to apply the brakes to a spinning wheel, rather than a mechanical limited-slip differential setup that you'd find in an Audi. 4MATIC is simpler, lighter and quieter, but not as effective in some situations.

ImInPA

Not to argue with Arrie, but I believe the Subaru system is the best. It is also the lightest (adding less than 70 lbs.) Subaru was doing it before Quattro. Subarus are simply unstoppable.

spyked

My main concern with 4MATIC is less about effectiveness and more about reliability/durability. Ever since 7G was introduced, things have gone downhill in terms of reliability due to Transfer Case issues.

pamiboy

Thanks for the explanation. So Audi and Subaru have better AWD systems. What about BMW, Lexus, etc. Are they similar mechanically to Audi or MB systems?

Arrie

The Audi Q7 that I used to have did not have any mechanical differential locks on it. It controlled the slipping wheels by applying brakes.


I don't know for sure but I have the understanding that the ESP (Electronic Stability Program), which in my 2010 E550 is called ESC (Electronic Stability Control, in my 2011 E350 it was ESP) was developed by Audi and it is used by other car manufacturers under license from Audi.


I'm not sure of this but I somehow learned that Audi developed and patented the system where you control the slip of the wheels by the brakes and not with differential locks. And this is a very clever way to do it and saves the car maker tons of money with not having to build the mechanical (or hydro-mechanical) locking systems in the transmission.


It eats up more brake pads and rotors but this is way less costly repair than repairing any kind of a differential locking system.

PilotAlan

As another said, it uses braking to divert power to wheels with traction. There's a 'gate' where the system allows a certain amount of wheelspin, then kicks into power shifting mode.


Watch those videos, they'll spin the tires very, very slowly, so the power distribution doesn't kick in. Then the car they want to come off the roller, you'll see the wheels spin much faster.


Give me control of the throttle, and I'll make any car I want 'win' the demonstration.