The summit of perfection with 4MATIC models

The current all-wheel-drive family of Mercedes-Benz passenger vehicles available in Canada consists of 37 models. This means that all-wheel-drive technology tailored to the respective vehicle class is always available – from the compact class model family and the vehicles of the C-, E-, S-, and CLS-Class to the comprehensive range of SUVs and cross-country vehicles of the GLA-, GLK-, M-, GL- and G-Class. Features common to all include high reserves of traction and outstanding agility, along with optimum handling safety and energy efficiency. The pinnacle of the all-wheel drive model range is occupied by a host of powerful high-performance models from Mercedes-AMG: the AMG Performance 4MATIC systems deliver driving dynamics on a high level, superlative driving pleasure, and improved acceleration from a standing start.

The all-wheel drive system of the compact class family

The members of the new compact class family from Mercedes-Benz namely the B-Class, CLA and GLA are available with the new generation of the 4MATIC all-wheel drive system with fully variable torque distribution.

Among the innovative components of this new 4MATIC system are the power take-off to the rear axle, which is integrated into the 7G-DCT automated dual clutch transmission, and the rear differential with integrated, hydraulically actuated multi-disc clutch. This set-up allows fully variable distribution of the drive torque between the front and rear axles. Additional benefits of this design are a lower system weight compared with the competition, and high efficiency. As with their front-wheel drive counterparts, all 4MATIC models also boast good energy efficiency.

The new 4MATIC is combined with the 7G-DCT seven-speed automated dual clutch transmission. The power flow to the rear drive train is provided by a compact power take-off unit (PTU) which is fully integrated into the main transmission and supplied with lubricant from the latter's oil circuit. This configuration gives rise to substantial weight advantages over competitor systems that branch off power by means of an add-on component with its own oil circuit. In conjunction with the friction-minimized tapered roller bearings, the PTU thus achieves an excellent level of efficiency.

The low system weight of the 4MATIC system is not attributable solely to the PTU. Other weight-stripping measures include a compact rear differential, inductively hardened, weight-optimized rear-axle half shafts and weight-optimized prop shafts. The system weight of this 4MATIC is up to 25 percent lower than in the all-wheel drive versions offered by the competition.

The two-piece drive shaft is decoupled in terms of vibrations. An axially moving joint at the front compensates for longitudinal movements of the engine transmission unit, while an elastic flexible coupling reduces the intrusion of high-frequency gearing vibrations at the rear differential. To minimize crash loads, the drive shaft is fitted with a telescoping element.

The electrohydraulically actuated multi-disc clutch integrated into the rear differential is responsible for the fully variable torque distribution. Fundamental operating principle: when the multi-disc clutch is open, the car is driven exclusively by the front axle. When the clutch is closed, the rear axle comes into play. However, the drive torque can be shifted in fully variable mode between front and rear axle according to the given situation (torque on demand).

The system pressure to activate the rear axle is supplied in milliseconds by a gerotor pump integrated into the rear differential. The pump is activated automatically as soon as only minimal speed differences arise between front and rear axles, and pressure control and therefore torque control to the rear axle is performed by means of a proportioning valve integrated into the rear axle.

The 4MATIC system is activated according to the basic principle of "as often as necessary, as rarely as possible". In other words: when the underlying conditions allow, the all-wheel drive compact models run in particularly economical front-wheel drive mode. As soon as the driving situation requires, drive torque is channelled to the rear axle as appropriate. The reverse process takes place just as quickly: as soon as additional drive torque is no longer necessary at the rear axle – e.g. in case of heavy braking manoeuvres with ABS intervention – the rear drive train is deactivated and torque is reduced to zero.

In case of impending understeer or oversteer under load, the drive torque is first of all distributed in such a way as to stabilize the vehicle. Only if these measures fail to have a stabilizing effect do the control systems adapted to the conditions of 4MATIC, such as ESP® or 4ETS, intervene and keep the vehicle on course.

AMG Performance 4MATIC for the top-of-the-line models from Mercedes-AMG

AMG Performance 4MATIC – this innovative variant of the 4MATIC all-wheel drive system remains the domain of the powerful compact models from Mercedes-AMG. It ensures an optimal mix of dynamics, traction and efficiency. This is made possible by fully variable torque distribution which ranges from purely front-wheel drive to a distribution of 50:50. When there is a so-called friction jump, i.e. when only the front wheels briefly lose grip on an icy surface, the entire torque is transferred to the rear wheels almost instantaneously. The three-stage ESP®, which is the hallmark of the AMG models, offers three tailor-made driving modes: "ESP ON", "SPORT Handling Mode" and "ESP OFF" can be selected at the push of a button.

The Mercedes-Benz GLA-Class: Multi-talented

Progressive in design, serene in day-to-day motoring and with good off-road capability: a wanderer between automotive worlds, the Mercedes-Benz GLA reinterprets the compact SUV segment in convincing style. It light-footedly masters all day-to-day challenges and is also robust enough for off-road excursions.

The GLA is equipped with DSR (Downhill Speed Regulation) and an off-road transmission mode. DSR is activated by a control button in the centre console, and assists the driver on demanding downhill stretches by maintaining a slow, manually selected vehicle speed within the physical limits when negotiating downhill gradients. This is done with the help of the engine and transmission control systems, and by targeted brake intervention.

When the off-road transmission mode is selected using the transmission mode switch, the shift points and accelerator characteristics are modified so that the requirements for driving on light off-road terrain, and particularly on loose surfaces, can be met. The head unit can also be switched to an On&Offroad display. The vehicle, steering angle, the on or off-road transmission mode and a compass are displayed there. The roll angle in degrees, the gradient in percent and activation of Downhill Speed Regulation DSR are also indicated.

Dynamic statement: the GLA 45 AMG 4MATIC

With the GLA 45 AMG 4MATIC the performance brand of Mercedes-Benz is making a dynamic statement in the strongly growing segment of compact SUVs. The combination of the powerful and distinctive design, exclusive appointments as well as superior engine power and driving performance is unique: the most powerful series-production four-cylinder engine in the world puts 355 hp and 332 lb-ft of torque on the road. The GLA 45 AMG 4MATIC high-performance SUV also shines with low emissions and fuel consumption figures. With a combined fuel consumption of 9.4 litres per 100 kilometres, the GLA 45 AMG provides proof that at Mercedes-AMG maximum performance does not come at the expense of environmental compatibility. The GLA 45 AMG 4MATIC also holds the pole position with regard to driving dynamics: it accelerates from zero to 100 km/h in 4.8 seconds and reaches a top speed of 250 km/h (electronically limited).

The all-wheel drive system of the C- and S-Class

The 4MATIC drive train used by Mercedes-Benz in this segment is one of the best-performing all-wheel drive systems available; the control systems are considered ground-breaking. The basic design concept, with the engine installed longitudinally and the integral transmission and transfer case unit, produces a compact, lightweight arrangement that minimizes frictional losses, heralding a number of benefits compared to other systems. Fuel consumption, for instance, is on a par with that of an equivalent vehicle with conventional drive system.

In concert with the dynamic handling control systems ESP®, acceleration skid control ASR and 4ETS, the basic 45:55 percent torque split between the front and rear axle ensures superior and predictable handling. When tuning the control systems, the engineers at the Mercedes-Benz Technology Centre made it a priority to ensure a defined level of understeer. This configuration manifests itself even under the most varying of road conditions, be it on a dry road, in rain or snow, on ice or on unsurfaced routes.

A double-disc clutch achieving a basic locking torque of approximately 37 lb-ft between the front and rear axle is fitted to the central differential. The clutch pack is permanently preloaded via a plate spring. In the case of spinning wheels on one of the two axles, a friction torque is transmitted to the axle spinning more slowly by relative movement of the discs. A sustained improvement to traction and directional stability of the vehicle are achieved through this principle of variable torque shift. Particularly in the case of low coefficients of friction between the tires and the road surface the traction and stabilizing effect of this so-called pre-lock clutch is clearly noticeable.

One stand-out feature of the 4MATIC all-wheel drive system is the extremely compact design of the transfer case and the lateral output to the front axle. The rear constant velocity joint of the prop shaft to the front axle was integrated into the transfer case's output gear, which significantly reduces the lateral space requirements of the transmission. In addition to reducing weight and improving fuel consumption, this means that the transmission tunnel can be kept very narrow. Consequently, the amount of legroom in the vehicle interior is the same as for the models with rear-wheel drive. The compact design also increases the natural bending frequency of the engine/transmission assembly, which has a positive effect on NVH and quiet-running.

AMG Performance 4MATIC all-wheel drive

The AMG Performance 4MATIC all-wheel drive system, which is available on the E 63 AMG, CLS 63 AMG, S 63 AMG, and S 63 AMG Coupe models, splits the torque between front and rear axle at a ratio of 33 to 67 percent. The rear-biased torque split provides the signature AMG high driving dynamics and superlative driving enjoyment as well as improved acceleration from a standing start. The all-wheel drive also enhances driving safety on wet or wintry road surfaces. Optimum traction is guaranteed by a multi-disc clutch with a locking effect of 37 lb-ft, which exploits the frictional connection potential of all four wheels to the full on snow and ice in particular.

The technical basis for the AMG Performance 4MATIC all-wheel drive system is a transfer case for the additional power take-off to the driven front axle. It requires no additional installation space, as it is integrated into the AMG SPEEDSHIFT MCT 7-speed sports transmission with minimum space requirements. The torque is transmitted from the power take-off via a prop shaft to the front axle. Power transmission from the front-axle differential to the left front drive shaft is effected via an intermediate shaft which passes through an encapsulated shaft duct in the engine oil pan. The compact and weight-optimized design results in a comparatively low level of additional weight for the all-wheel drive system of only 70 kilograms, which also helps to reduce fuel consumption and exhaust emissions.

Traction with tradition: Start of 4MATIC in the 124 model series

The 4MATIC all-wheel drive system celebrated its world premiere at the Frankfurt/Main International Motor Show in 1985. One year later, Mercedes-Benz presented the innovation in the then current E-Class of the124 model series. Delivery of the first models began in spring of 1987.

Besides the complex control electronics, the 4MATIC all-wheel drive system consisted of a complete additional front-wheel drive system with transfer case and differential, the latter of which was integrated into the oil pan due to space restrictions.

This all-wheel drive system was available for the six-cylinder models. The considerable technical complexity of this perfected drive system was reflected in the sales price: in 1987, the 260 E 4MATIC, 300 E 4MATIC, 300 TE 4MATIC, 300 D 4MATIC and 300 TD Turbo 4MATIC models demanded a price premium over their rear-wheel drive counterparts of more than 6100 Euros in today's money.

Even the best all-wheel drive is no substitute for winter tires

Like any other all-wheel drive system, the 4MATIC versions have to abide by the laws of driving physics. The fundamental rule is that a tire is only able to transfer a certain level of overall force to the road surface. If a particularly high degree of longitudinal force is required during acceleration or braking, for example, the available lateral force is reduced. When cornering, the reverse applies: now a large amount of lateral force is required to keep the vehicle on course, while the longitudinal force potential is restricted. The engineers' skill in designing the drive mechanism and fine-tuning the control systems lies in their ability to exploit these correlations in such a way as to ensure the best possible handling characteristics under all conditions. The frictional coefficient µ describes the physical grip between the tires and the ground. This figure is high on a dry road (µ = 0.9) and low on a snow-covered road (µ = 0.3).

Despite all the engineers' efforts, ultimately it is the drivers themselves who determine how safe they are out on the road. They should always adapt their driving style to the prevailing wintry conditions and ensure that their vehicle is suitably equipped. Winter tires are absolutely essential in this regard.

About Mercedes-Benz Canada

Mercedes-Benz Canada is responsible for the sales, marketing and service of the Mercedes-Benz and AMG passenger vehicles, Mercedes-Benz Vans and smart. Headquartered in Toronto, Ontario, Mercedes-Benz Canada Inc. employs approximately 1,500 people in 23 locations across Canada. Through a nationwide network of 13 Mercedes-Benz owned retail operations and 43 authorized dealerships, Mercedes-Benz Canada sold 40,555 vehicles in 2014. This represents the best year ever for the company and has positioned Mercedes-Benz as the top luxury manufacturer in Canada.

For more information, please contact:

JoAnne Caza               416-847-7550  joanne.caza@mercedes-benz.ca

Nathalie Gravel           416-847-7509  nathalie.gravel@mercedes-benz.ca

Further information from Mercedes-Benz is available on the internet at: www.media.mercedes-benz.ca