Posted on: 14 July 2016
The promise of extra traction in wet and snowy weather has made all-wheel drive (AWD) a popular option for many car buyers. However, the addition of all-wheel drive can make towing a vehicle so equipped a bit complicated. The following explains why it's important to err on the side of caution when towing an AWD vehicle. You'll also learn a few safe ways to get the job done, whether you're towing your own vehicle or having a towing service do the work for you.
Understanding AWD and 4WD
Before getting down to the nuts and bolts of AWD, it's important to clear up a bit of confusion concerning the term "all-wheel drive." That's because it's commonly used interchangeably with "four-wheel drive" (4WD), which works similarly to AWD in some respects. However, there are a few important differences between AWD and 4WD:
- 4WD systems are generally optimized for off-road use. Part-time 4WD systems allow the driver to manually engage all four wheels at low speeds. Full-time 4WD systems work similarly to AWD, allowing drivers to keep all four wheels engaged. Most 4WD systems use front and rear differentials, plus a transfer case for engaging the front and/or rear axles.
- AWD systems are optimized for on-road use. AWD systems typically use front and rear differentials just like their 4WD counterparts, but with the addition of a viscous or electronic coupling to split power between each set of axles or even individual wheels. Most AWD systems are also permanently engaged to varying extents, making it impossible to disengage without removing a driveshaft.
The Problem With Towing AWD Vehicles
When it comes to towing a vehicle on two wheels, common wisdom dictates that the vehicle being towed shouldn't be towed by its drive wheels. Even if the vehicle is left in neutral, towing a car by its drive wheels can cause significant damage to the transmission. With a front-wheel drive (FWD) vehicle, that means towing the car with its rear wheels on the ground. For a rear-wheel drive (RWD) car, the opposite applies -- the car must be towed with its front wheels on the ground (with the steering locked for safety) or with the driveshaft removed while its rear wheels are on the ground.
For an AWD car, however, that common wisdom flies out of the window. Towing a vehicle equipped with a permanent AWD system on two wheels could result in damage to the coupling, as well as the transmission and various other drive components.
How to Tow an AWD Vehicle without Damage
When dealing with AWD vehicles that need a tow, keeping it off the ground is usually the best strategy. For this, you'll need a flatbed tow truck or a flatbed trailer. Trailering or towing an AWD vehicle on a flatbed is the easiest and often safest choice of moving such a vehicle without causing thousands of dollars in damage to its drivetrain. When flatbed tow trucks or trailers aren't available, many tow truck and crane services resort to tow dollies to transport AWD vehicles while keeping their wheels above ground.
Keep in mind these aren't the tow dollies normally offered by moving truck rental companies. These tow dollies consist of an inline pair of small wheels attached to a metal frame. The frame is placed against the vehicle's wheel and the two pairs of wheels are linked together with a set of aluminum axles. Using a long bar and plenty of leverage, the axles are lifted into position, which in turn cradles the wheels between the axles and lifts them off the ground.
Both methods are preferred for towing AWD vehicles, since it minimizes the likelihood of damage to the vehicle's drivetrain components.Share