• Tow hooks: Large tow hooks are positioned front and/or rear to allow simple tow-strap connection for rescuing a stuck truck, be it yours or someone else's. Consider them more cheap off-roading insurance. As a factory option, tow hooks are mounted at a strong point on the frame and are airbag compatible. (Tow hooks and winches can change front crush dynamics and trigger an airbag deployment early or late.) Rear tow hooks are less common, but a tow hitch can substitute with the proper recovery accessories.
• Traction assists: These come in both electronic and mechanical forms. Mechanical traction assists include limited-slip differentials and locking differentials. The former provides a minor increase in rear-axle traction, but may require more maintenance, as they are always "on" and operate automatically. A true locking differential connects both tires on an axle together so that even if one tire is off the ground the other one can provide motive force. Most operate only in low-range and only when activated by the driver. Some vehicles, such as a few Toyota trucks, offer a lock for the rear axle only, others like the new Dodge Power Wagon, Jeep Wrangler Rubicon, and Mercedes G-Class offer one for both front and rear. Electronic traction assists use throttle intervention and the ABS system to keep a wheel from spinning and, like a limited-slip, they provide increased traction and can be used on any road surface including dry pavement. Some systems work only on the rear wheels, others on all wheels, but all work automatically. If you're stuck or sliding in the snow and hear a buzzing, vibration, or clicking noise, the system is actively working. Although sufficient for most drivers, electronic traction assists cannot equal a locking differential when it comes to back-country traction. In fact, several good on-road systems, such as those on the Cadillac Escalade and Mercedes-Benz M-Class, are easily overwhelmed off road.
• Hill-descent systems: These use the ABS controls to automatically apply brakes and limit downhill speed as long as the tires have traction, typically less than 4 to 5 mph in low range and less than 10 to 15 mph in high range. These systems, such as those found on the BMW X5, Land Rover LR3 and soon the Jeep Grand Cherokee, can make descending large, loose-dirt hills much easier and safer. Hill-descent control typically can be turned on/off like a conventional traction-control system. When activated, and the vehicle is in an appropriate low-speed descent, the systems work with brakes, engine management, and transmission (if auto) to effectively creep down the hill. With only conventional engine braking, speeds can climb and anti-lock brakes can be overwhelmed as they fight for stability, leading to sliding.