4WD / AWD Vehicles Today
Audi and Subaru continue to successfully market all wheel drive vehicles and both marques actively compete in motorsports to show the worth of their technology. The Audi A4 quattro has been particularly successful in demolishing its two wheel drive competition in seven major touring car series last year despite severe weight handicaps. The Subaru Impreza turbo has been extremely successful in World Championship Rallying. The Mitsubishi Eclipse GSX has been less successful in the marketplace, with the vast majority of buyers opting for the front wheel drive version. Die hard Porsche enthusiasts prefer the rear wheel drive version of the 911 to the all wheel drive version. Four wheel drive is increasingly outlawed in competition because they tend to do too well.

With the success of sport utility vehicles the market for high performance all wheel drive vehicles will remain tiny. One could only hope that competition among the makers will eventually force all the SUV makers to bring their technology up to all wheel drive levels. This is starting to happen but at a very slow pace.

VW recently redesigned the Passat and based it on Audi A4 mechanicals. Since it was using a stretched version of the A4's floorpan, it made economic sense to use Audi's quattro system for the all wheel drive model, rather than to create a unique all wheel drive floorplan using the syncro system. Thus the "syncro" moniker becomes merely a generic term to distinguish an all wheel drive VW from a two wheel drive variant. This is not the first time that VW has used Audi quattro mechanicals. In the mid 1980's, Americans could buy the VW Quantum Syncro, which not only used the Audi 4000CS quattro's floorpan, but also the trademark inline 5 cylinder engine, mounted longitudinally ahead of the front axle.

For the 1999 model year VW has upgraded its AWD system from the viscous coupling based system to a computer controlled clutch developed by the Swedish company Haldex. The advantages include added simplicity since the extra clutch needed for braking can now be eliminated. Also, more precise control of the torque splits and a greater transfer ratio is possible. Derivatives of the AWD fourth generation Golf, (now renamed the "Golf 4Motion") such as the Audi TT and the A3 quattro will use this system. Note that this is still a part time, automatically enganging four wheel drive system. The quattro name, which used to have special significance is now being diluted by marketing expediency. Considerable confusion has arisen from the naming corruption by the two companies.

In yet another twist, Subaru has for many years been quietly offering radically different AWD systems in the same car, depending on the transmission choice. The manual transmission Legacies and Imprezas use a full time system that is split 50-50 with viscous couplings for limiting slip. In the automatic transmission versions, however, the system is a part time, computer controlled, automatically engaging system in some models and a full time uneven torque split with computer controlled locking in other models.

Mitsubishi has quietly continued to offer its four wheel drive GSX, now with rear limited slip and ABS together in the same package, even though its relatively low sales figures mean that it is far from a profitable model. Advances in ABS technology mean that the coexistence with VC systems is far less troubling than before. Porsches, for example have different ABS specifications depending on whether the model is four wheel drive or two wheel drive.

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