21. There is no wasted sheet metal, no four-wheel-drive systems whirring away unnecessarily underneath. 22. But what is best about this new Jeep is its new all-wheel-drive system . 23. Chrysler engineers said the feature would have made the optional four-wheel-drive system impossible. 24. "Full time " four-wheel-drive systems are the most convenient and expensive. 25. Four-wheel-drive systems have been around about as long as there have been cars. 26. The Bravada that I drove had Oldsmobile's Smart Trak all-wheel-drive system . 27. Modern systems use electrical control and drive systems for the winches. 28. A full hollow shaft ( folded cardan ) drive system is also optional. 29. The most sophisticated and expensive four-wheel-drive systems are often called permanent. 30. The drive system was based on the one used in the French Tracta.
