When driving in slick conditions it is my experience that 4WD offers the best stability. This followed by FWD and last RWD. When driving a RWD truck it is best practice to put it in 4WD under slick driving conditions. The benefits of having all four wheels driving include the pulling action of the front tires to limit the washout effect of spinning rear tires.
This is incorrect. In a standard RWD vehicle only one rear wheel drives while in a standard FWD vehicle only one front wheel drives. Similarly, in a standard 4WD vehicle only two wheels drive, one in the front and one in the back. This is done of course due to relative left/right rotation in a corner, where the outside wheel has to travel a longer distance relative to the inside wheel. Regardless, 4WD doubles the traction available vs FWD or RWD.
Furthermore, it used to be that the wheel with the least resistance drove the vehicle. That's why when getting stuck one wheel would spin (the one with no traction) while the other stayed still. In many newer vehicles this has been reversed.
I've owned all three. My Cherokee, which was built specifically for off-roading (Easter Jeep Safari, Dakota Territory Challenge, etc.) had air locking differentials (ARB Air Lockers) which I could independently engage in the front, rear or both to get true 4WD while again, doubling the traction available in a standard 4WD vehicle. I chose ARB air lockers over mechanical lockers specifically because I live in winter snow and ice. I wanted to be absolutely sure that in icy conditions I could totally disengage the left/right locks. Using true 4WD in icy conditions (as opposed to AWD or standard 4WD) is likely the worst possible thing you could do. Your ability to turn the vehicle on ice is reduced to nil.
That said the best options in order are generally 4WD, FWD then RWD. I say generally because weight distribution plays a role. A front engine RWD vehicle is generally worse than a mid or rear engine RWD vehicle. My current daily driver is a 1986 Pontiac Fiero V6 that I've driven in the winter for the past 28 years (40/60 F/R weight distribution). It's really a delight on snow (as long as it's not too deep) and ice as the front wheels wash out before the back end ever thinks about letting loose.
Anyway, I grew up in northern MN near the Canadian border in an era where RWD (or for some more fortunate, 4WD) was the only option. I got used to driving in the worst of conditions. While I admit to being more aggressive in bad conditions than most, I feel I have the experience to drive within the limits of myself, my vehicle and the conditions so as not to put others in harms way.
