Mercedes CLA Forum banner
1 - 4 of 4 Posts

·
Registered
Joined
·
12 Posts
Discussion Starter · #1 ·
Has anyone been able to find out more information on the CLA45's AWD system? The new Audi S3 uses a Haldex 5 system which is pretty sophisticated. Mercedes doesn't say much at all about theirs. Anyone know for sure if it is Haldex of some kind?

All I can find is what they say in their advertising, it's primarily FWD, with up to 50% of the power going to the rear wheels as demanded.

Even on the Haldex system that Audi uses, I can't find any documentation that states how the power is put down. Some of the Audi guys claim it's up to 100% RWD as needed. However, I can't find anything official that backs that up.
 

·
Registered
Joined
·
12 Posts
The Haldex I believe is the cheapest route except its an upgraded electronic spool? The Evo and STI uses proper differentials in the center thus costing $40,000.00 with crappy interior, NVH, but a great AWD system and chassis.
 

·
Registered
Joined
·
12 Posts
Discussion Starter · #3 · (Edited)
Did some more research today and found the information I was looking for. If you are interested about the AWD systems on the CLA and the S3, here's what I found.

Per the literature from mbusa the CLA uses an AMG performance 4Matic all-wheel drive system. The 4Matic was developed back in 1985 in conjunction with Steyr-Daimler-Puch (now Magna Steyr). On the CLA up to 50% of the power can be transferred to the rear wheels on demand.

Pretty thorough write up on wikipedia about 4Matic.

http://en.wikipedia.org/wiki/4Matic

The new S3 uses Haldex.

Starting from 1998, "quattro" has become just a trade mark and it does not guarantee that a full-time all wheel drive system with Torsen differential is used on the vehicle any more. Now, vehicles with transverse engine mounting (Audi A3/S3 quattro, Audi TT quattro) are equipped with Haldex automatic all wheel drive. The same type of automatic all wheel drive is used on VW Golf/Bora/Jetta 4motion (199:cool:, VW Sharan 4motion (2001-) and other Volkswagen Audi Group vehicles with transverse engine mounting - Seat and Skoda.


Haldex V is proactive and reacts nearly instantly to any wheel slippage. It also can transfer up to 100% of the power to the rear wheels.


http://www.awdwiki.com/en/quattro+evolutions/

There is some decent info on Haldex on the Borg Warner site. December of 2010 they acquired the AWD Traction Systems of Haldex.

"​Haldex Generation V is an electronically controllable all-wheel drive coupling for cars. The Haldex GenV includes an electronic control unit with vehicle dynamics software that can be customized to meet each carmaker's particular desires in terms of driving characteristics.​
The front and rear axle of the car is connected via the wet multi-plate clutch which makes it possible to vary the torque distribution between the two axles. As the function of the Haldex GenV is independent of the differential speed between the front and rear axle, full locking torque, if needed, is available at any given time and speed.

When starting the vehicle, the electrical pump in the Haldex Gen V is started, swiftly providing the system with pressurized oil and thereby making the system ready for operation. The pump sets the pressure to the piston which in turn compresses the disc package. The level of pressure set depends on the torque level needed and on the driving situation. In traction/high slip conditions, a high pressure is delivered. In tight curves (i.e. parking) or at high speeds, a much lower pressure is provided."

Products
 

·
Registered
Joined
·
12 Posts
AutoZine Technical School - Traction

On my Lancer Evolution or Subaru STI they use an electronic center differential with computer control clutches. Three differentials total and i'm sure being a rally car it is designed to go fast.

On the Haldex system only the clutches are being used as the differential and the differential is not present. It amazes me how the clutch would not wear and break over time with hard AWD launches? It is a cost saving system not a racing system which is why in the past I purchased both the STI and Evo over the vw. However, I did give into the TTRS since they revived the 5 cylinder turbo:)
 
1 - 4 of 4 Posts
Top