They all have the viscous plate pack type coupling on the diffs nose.
You can see it in your image (oily bit to the left with the drain highlighted).
It seems Fiat changed supplier in 2008, from a GKN coupling to a Magna Steyr one.
These Magna Steyr do all appear to have an electropneumatic coupling.
I stole this to explain
"The unit can be viewed as a hydraulic pump in which the housing and an annular piston are connected to one shaft and a piston actuator is connected to the other.
The two shafts are connected via the wet multi-plate clutch pack, normally unloaded and thus transferring no torque between the shafts.
When both shafts are rotating at the same speed, there is no pumping action. When a speed difference occurs, the pumping starts immediately to generate oil flow. It is a piston pump, so there is a virtually instant reaction with no low-speed pumping loss.
The oil flows to a clutch piston, compressing the clutch pack and braking the speed difference between the axles. The oil returns to the reservoir via a controllable valve, which adjusts the oil pressure and the force on the clutch package."
So instead of the pack of plates slipping in oil then gripping together (old GKN system).
The difference in shaft speed actuates a pump to use fluid to compress the plate pack together, the greater the difference, the harder it pumps, the greater the pressure on the pack, the more torque it allows through.
This way the action is more instant.
Now it appears there are addition functions to the Cross and later 312 model 4x4's.
They have the ability to over ride it's self and actuate the pump before it detects differing shaft speeds, so by selecting a setting in the cabin, it actuates the pump and sets the system to 50/50 from the off.
The Climbing manages it's self.
