4-Wheel Drive vehicles and how they work. This is part-1 of the series, 'The Complete Guide to Four-Wheel Drive'. This book covers more than just the basics and includes four-wheel drive vehicle design, what makes some good off-road and others not, how suspension design affects performance both on and off the road and much, much more including of how engines in four-wheel drives affect their abilities, what suspensions work best for what terrain, and buying used 4WD vehicles with confidence. The equivalent of 38, A5 pages.