When I was a working stiff, the Bell System supplied us engineers with nice new front wheel drive cars to do our field work. They were fast, reliable, and fairly economical, but useless in certain situations. On steep loose gravel roads or driveways, they had no traction. All the weight went to the back wheels and the front wheels would slip so bad you could not go forward. On one occasion, I was approaching a blind curve from a steep driveway on to a major highway that carried a large number of double fuel tankers. Every time I slowed down to see if traffic was coming, I could proceed no further. I had to back completely down the driveway. On the fourth attempt, I went up backwards and backed on to the highway. I do not want to repeat that again! During the winter, if the roads were slick and the grade was steep, the only way up hill, even with chains, was in reverse.
I have seen many two wheel drive pickups with large travel trailers pull on to grass covered camp grounds. When they attempted to leave, the damp grass caused one of their wheels to spin and they went no where. A four wheel drive truck even with out a limited slip differential, easily pulls both the two wheel drive truck with it’s trailer out of trouble.