This was an SRT 10.....the one with the 500hp Viperengine, they don't come in 4wd
Besides that , hitting an 'icy spot' (whatever that is) going 140 kph I doubt 4wd will save it.
Another thing you fail to realise is that 4wd on these trucks is infact a on/off systhem designed for off-road /'real' snow surfaces and not an AWD systhem for roaduse like you get on the average SUV thingie these days.
Meaning that it will actualy become LESS roadholding when you have it engaged on a hard surface (the road was clear in this case , minus the 'icy spot') , not to mention it will eat up your front tyres and you will pretty much fuck up every moving part on the truck going motorwayspeeds with it on.......