The new four-wheel-drive Freemont, which will be another rebadge of Dodge's 4WD version of the minivan, will come to the European market with the same engines as the 2WD version, the 170 HP 2.0 MultiJet 2 and the 280 HP 3.6 V6 petrol engines, both with a 6-speed automatic gearbox. With European minivan customers not being generally noted for requiring four-wheel-drive on what is a "school run" minivan this new version is likely to see very little demand. No pricing have been announced yet.

The 4WD system is sophisticated yet very simple to use, designed to control the vehicle in extreme conditions in total safety. The 4WD four-wheel drive system is on-demand, and it is equipped with an electronic control unit which uses slip sensors to detect the grip of the four wheels and decides when to transmit traction to the rear. The system intervenes on surfaces where the wheels may not have an efficient grip (mud, snow, ice...) to ensure maximum traction and no limits to the routes the vehicle can take, or in the case of asphalt surfaces, to ensure additional traction and greater security on bends.

Specifically, the electronic system modulates the torque transfer through the use of electronically controlled coupling (ECC). The system contributes to containing fuel consumption since it only operates on demand, thereby minimising the friction caused on the engine. In addition, ECC on the 4WD system is more flexible and more accurate than a viscous coupling or a Torsen system.

In addition, the control unit also interfaces with the ESP and the traction control system. Remember that the AWD system does not replace traction control since it only intervenes in circumstances where the traction varies between the two axles (for instance, when the front wheels are on ice while the rear wheels are on dry asphalt or on steep hills). On the other hand, in the event of different grip on two sides of the vehicle, the ESP kicks in.

How it works

The four-wheel drive system does not require any controls or input. In detail, it is passive for many driving conditions and traction is only transmitted to the front wheels. The system operates by optimising traction and drivability using the following strategies:

Preventive control: in this phase, the system acts without considering wheel slip but only analyses the driver's action on the pedal according to the driving conditions. If the driver is requesting a lot of power, the 4WD traction is automatically activated, transferring a high percentage of power to the rear wheels. This prevents the front wheels from slipping, since the necessary power is transmitted through all four wheels.

Slip control: a second operating mode uses the feedback from the wheel speed sensors to determine the appropriate torque to transfer. When the front wheels slip, the ECU (Electronic Control Unit) activates the ECC in order to start transferring power to the rear wheels. If the car is to start with the front wheels on ice (or surface with a poor grip) and the rear wheels on a dry surface, the system sends more torque to the rear wheels in order to reduce slippage. The power to the rear wheels is also modulated in the event of lost traction at constant speed. For instance, during "aquaplaning" on a puddle of water, the system is capable of remodulating the power sent to the rear wheels, since higher values would not be necessary.

Affects drivability at moderate speed: the 4WD system is used to optimise the vehicle dynamics. On the Fiat Freemont, the ECU controls the torque on the rear wheels to improve drivability even between 40 and 105 km/h. In this speed range, the system uses the torque for the rear wheels on bends and when accelerating to improve steering and make drivability more neutral. This is achieved via the electronic control system, which is preferable to viscous couplings that transfer the torque to the rear wheels only after a certain degree of slippage of the front compared to the rear.