The R350 gets its juice from a 3.5-liter V6 that boasts 263 hp and 258 pound-feet of torque. Powering the R500 is a 5.0-liter V6 that commands 302 hp and 339 lb-ft of torque. Both engines are mated to Mercedes' outstanding seven-speed automatic transmission. All Mercedes-Benz R-Class models are equipped with an all-wheel-drive system that in normal driving situations applies power in a 50-percent front/50-percent rear distribution.