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Tips for Towing Safely

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Although this isn't necessarily related to diagnostics or repair, it's something that can lead to a need for diagnostics or repair if done incorrectly. Towing is a capability that many vehicles, especially truck-based pickups and SUVs, are purchased for. Yet many people aren't doing it right and are exposing themselves and others to safety hazards and their vehicle to possible early breakdown or worse.

Proper towing requires that you have some basic equipment installed on your vehicle, not all of which will be factory standards. A tow hitch attached to the vehicle's frame, for example, can be purchased as a factory option, dealership installation, or aftermarket addition. In all cases, it should be installed correctly and without compromising the integrity of your truck or SUV's frame. Welding to your car's frame, for example, can change the metallurgy of the frame and make it weaker or more brittle. Be sure your hitch kit is properly installed.

Two figures to know before you tow: tongue and gross vehicle weights. The tongue weight of a trailer is the amount of weight it puts on the back of the vehicle when hitched. This is the "downforce" weight of the trailer on the rear of the truck or car. Most owner's manuals of vehicles capable of towing will have two towing numbers listed: tongue and pull capacity. The tongue weight is what you're after while the towing capacity (pulling weight) the vehicle is capable of safely hauling is a measure of the weight of the trailer and its cargo. That, plus the vehicle's total weight, is the gross vehicle weight (GVW) you'll be hauling. You need to know GVW because that, more than anything, will affect how well your vehicle will handle on the road and will decide where you can and cannot take your trailer.

For example, a small SUV pulling a tent trailer with a total combined GVW of 9,000 pounds can probably traverse most dirt roads going into a lake area for camping. A big pickup truck pulling the same trailer, however, might have a GVW of 11,000 pounds and be too heavy to drive over the muddy dirty road into the campsite without compromising the 10,000 pound limit of the small bridge you'll have to cross. Many bridges, roadways, and other places you might go will have gross weight restrictions for safety. Knowing your GVW can help you plan your route safely.

Tow less than capacity, not at or more. If your vehicle is rated at 10,000 pounds of towing capacity, make sure you're hauling less than, not more than that number. A trailer rated at 9,000 pounds can quickly weigh more than that once you've added your gear.

Hitch up properly, including plugs. "Don't shotgun the marriage if you can help it," old time truckers used to say. This means to take your time and hook up your trailer properly, double-checking all connections. Every time. Ball hitches will often have the capability to "drop" or "rise" to meet the receiver on the trailer. Use the right amount so that the trailer is as level as possible. Further, make sure you're using the right hitch for the job. A 1-7/8 inch ball hitched to a 2-inch receiver is a disaster waiting to happen. Once your hitch is engaged, make sure the pins and locks are in place and securely doing their jobs.

Safety chains are a must and should not be ignored. It's best to hook them up in a "cross" pattern (left to right side, right to left side) because their job is to keep the trailer attached should the hitch come loose for any reason. This reduces accidents for other motorists since a loose, uncontrolled trailer, can really wreak havoc on a highway. The crossing of the chains gives the chance that the loose hitch will "cradle" in the cross, reducing damage and keeping the trailer more level and thus controllable.

Lights, brakes, and more lights. Always check your trailer lights after plugging them in. ALWAYS. Have a friend press the brake pedal, run the turn signals, etc. while you walk around the trailer to make sure all of the lights are working. If not, find out why before you leave.

Braking is another concern. Heavier trailers should have trailer brake controls that you can operate from the driver's seat. Most full-sized pickups and heavy-duty trucks have trailer brake controls as an option and if you plan to tow, you should have that option installed. Adjust the gain every time you hitch up a trailer, even if you pull the same one all the time. You never know if things have changed and you don't want to find out while going downhill at 65 mph somewhere. Adjusting the gain is simple: pull the trailer to about 25 mph then slowly stop as you normally would. The trailer's brakes should be taking most of the weight. You want to feel that the trailer is doing most of the work, but not dragging on the truck otherwise.

Distance is good. Keep your distance from other vehicles. Tailgating is a bad habit to begin with, but add in the weight of a trailer and the longer stopping distances (and increased damage in a wreck) and you really can be hazardous. Leave more distance than necessary if you can. Every couple of thousand pounds is another car length you'll need to stop at in-town speeds (never mind the freeway). Distance also gives you the opportunity to react to things happening with your own rig like sway, which can be controlled by slightly speeding up or slowing down.