In fairness to the OP, I don't see anything wrong with 4motion being offered as an option, although I agree its probably unlikely.
Generally 4WD/AWD drivetrains into three basic groups: full-time 4WD, part-time 4WD, and all-wheel drive (AWD).
As the name suggests full-time 4WD operates at all times. Torque is supplied to all four wheels, with various options affecting the operation of the drivetrain. When on normal roads, front and rear axles are split by a differential, allowing different speeds to be applied - useful when cornering, for example. On rough roads and tracks, the 'diff lock' can be applied to lock up the centre differential and restricts any rotational difference between the front and rear axles, to gain maximum traction. 'Low range' can also be used in extreme offroad conditions and on steep inclines, to provide a torque multiplying effect similar to the lowest gearing on a mountain bike.
Part-time 4WD is the original 4WD system and the most basic. In normal conditions the vehicle is driven in two-wheel drive, usually powering only the rear wheels. 4WD mode can be selected either by a separate mechanical lever or by an electronic switching system. When 4WD is selected, torque is split evenly between the four wheels. Part time 4WD vehicles tend not to have differentials between the front and rear axles, limits the use of 4WD to offroad use because use of this feature on bitumen surfaces (where tyres have good traction) can cause excess stress and damage to the drivetrain (often called wind-up). Most vehicles of this type have the option of 'low range' for extreme off-road conditions.
All-Wheel Drive is in some ways similar to the full-time 4WD system in that it also sends torque to all four wheels constantly. These systems never have the option to operate in two-wheel drive, and unlike the 4WD systems, the differential between the front and rear axles cannot be locked. The differentials do, however, have ability to limit slippage between the axles if a low traction situation is encountered. Usually this ability is provided with a differential known as a viscous coupling although more recently a similar outcome has been achieved by using electronically-controlled hydraulic or electro-magnetic 'clutch' systems. AWD systems also lack the 'low range' feature which is common in most 4WDs.
The AWD system is less effective and more fragile than the 4WD system in a situation where high torque is required. Indeed, the viscous coupling units simply cannot satisfy high torque demands when the vehicle is offroad. AWD vehicles tend to be more 'car' like than obvious offroaders.
That said, limiting slippage between axles can and does improve road safety. Sure, it might only be useful once in a blue moon, but I don't think it's any less useful than any other safety fitting (I might never use airbags, doesn't mean I don't mind 'em).
2013 CC 130TDI Night Blue Metallic with Driver Assistance Package, Park Assist 2, Walnut Trim and Ambient Lighting, Front Active Climate Control Seats, Towbar, and Dynaudio Premium Audio.
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My previous ride - 2005 Golf Comfortline DSG 2.0 TDI
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