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Trailer Towing Tips Problem And Solution - Knowing Towing

Posted in How To on July 1, 2009
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This Suzuki Equator can handle up to 6,500 pounds with the right hitch, so it can readily tow a 4,100-pound bass boat. However, only the 4x2 V-6 Extended Cab with the Sport Package and automatic transmission is actually rated to tow 6,500 pounds. Like most pickups, the "max tow rating" used in advertising depends entirely on the configuration of the truck and drive train, and will often specify use of a weight-distributing hitch.

Your day in court is not going well.

Your insurance company has run for cover, saying they had no idea you habitually operated in violation of state law.

The manufacturer, also named in the case, sends a team of seven lawyers who take no responsibility for equipment failure, blame you, say you were warned, that you were negligent, that it was all your fault, and certainly none of theirs.

The plaintiff's attorney brings the victim into court in his wheelchair, and easily wins the case.

The judge slams his gavel, and the opposing lawyer files paperwork to attach your house, your car, your retirement fund and force you to spend the next 20 years paying restitution.

Then you wake up. You're OK...thank heaven.

Actually, this nightmare scenario is not so farfetched. Whenever you tow something, a whole new set of laws, rules, standards and requirements take effect, and whether you realize it or not, it's your legal responsibility to operate within them. Requirements vary from state to state; equipment varies from trailer to trailer, capability varies from truck to truck. The one constant is that when something goes wrong, they can throw the book at you.

We've all rationalized towing a load using an inadequate truck or trailer by saying "It's not very far" or "I'll just go really slow" or "I think it will be OK". You get used to doing it, and one day you decide to go a little farther, a little faster, and boom!, you just cost yourself a lot of money.

Sometimes it's on the driver-side door, sometimes it's on the doorjamb, but there should always be a vehicle ID sticker that identifies the exact weight capacities of a given vehicle. That's the information that matters for your particular vehicle.

Problem #1:
You Have No Idea What Your Truck Is Actually Rated To Tow
Maybe you bought it from a guy who said it "oughta be able to tow that." Maybe you're going by what the salesman in the dealership told you. Or maybe you never checked the owner's manual to pin down which version of the hundreds of different pickup truck models you have, and what that means in terms of rated capacities. Maybe you've seen other people towing something that looks like your load using a truck that looks just like yours. Unfortunately, when it comes to towing on public roads, ignorance is not bliss.

What To Do:
First step, check the Vehicle ID sticker on the inside of the driver-side door jamb. It will say what the Gross Vehicle Weight Rating (GVWR) is, how much weight the front axle can carry, and how much the rear axle can carry. It also specifies the exact tires you must use, the exact wheel, and the exact psi the tire pressure must be.

Usually, the numbers on the door are much less than the numbers bandied about in sales literature. When the ad says your truck can tow 10,000 pounds, there is a little asterisk there, which says "when properly equipped."

You'll have to check the owner's manual to find out what "properly equipped" actually is from the manufacturer's point of view. There you will find charts that show all the different variations of the truck you own, and what they can handle. Look up the Gross Combined Weight Rating (GCWR), the Gross Trailer Weight rating (GTWR), and recommended tongue weight, given the type of hitch you are using. (This information, if you have lost the Owner's Manual, is usually available at the manufacturer's website.)

That will tell you how heavy a trailer you can tow, how much cargo you can put in the tow vehicle, and how much tongue weight your combination can handle, and what hitch you must use. Bottom line, the number is probably less than you think.

Problem #2:
You Have No Idea What Your Trailer Or Truck Actually Weighs
Actually, hardly anyone knows what the weight of their trailer is, or how much all their gear weighs. Chances are, it's more than you think, meaning it's likely you are overloaded in some way or other. Remember, the weight of everything in your tow vehicle--passengers, food, tools, and gear--takes away from the amount of trailer weight you can safely manage. You'd be surprised how much weight a pickup truck can gain when a party of four heads out camping.

The first step to towing safely is to do what the pros do--visit a certified scales. For 10 or 15 bucks, you can find out what your truck weighs when loaded, what your trailer weighs with everything in it, and the two together weigh. With that, you can compare to the manufacturer's published capacities, and plan accordingly.

What to Do:
This is easy--just go to the certified truck scales. You can find them in the phone book or on the web. When you get there, talk to the scales operator so he understands you want to get a weight of the trailer alone (gross trailer weight); plus the weight of the truck alone (gross vehicle weight), plus the weight of the combination (gross combined weight). That's three weights. That will be a hassle, and you might need some help to unhook the trailer on the scale, but it will be well worth the exercise. Should cost you around $15, and you'll be done in 10 minutes.

The good part about weighing your trailer, aside from being safe, is you now have certified proof that you are operating within the recommended weight limits. In a court of law, that's a good thing. It's also a good thing in case your transmission goes south, or an axle burns up, for warranty purposes.

Obviously, when you go weigh your trailer, have all your gear inside. If it's a boat, that means all your camping gear, fuel, spare prop, fresh battery, skis, fishing tackle, safety gear, drinking water--all of it.

Problem #3:
Equipment Combinations Affect Tow Ability
Sounds stupid, but reading the owner's manual is not as easy as it sounds. Tow ratings for every truck vary by body type, engine, transmission, drive system, even the weight of the options. As an example, take the case of the Suzuki Equator, rated to tow 6,500 pounds. By checking the owner's manual, you will see it indeed can handle 6,500 pounds, but only the V-6 powered, Extended Cab, 4x2 Equator, with the automatic transmission and Sport package. All others are rated to tow less, and in some combinations, much less. A four-cylinder 4x2 Equator, with the manual transmission, is rated to tow 3,500 pounds, no more. This is not at all unusual--the maximum tow rating usually applies to a very narrow range of configurations.

What to do:
Check the fine print in your owner's manual to find out what the rating is for your exact model. There will be a chart that helps you sort through the different variations to find your actual capacity.

A closer look at a typical Vehicle ID sticker shows that it has the VIN number for your vehicle, plus the gross axle weight rating for each axle, plus the gross vehicle weight rating, given certain wheels, certain tires, at a certain tire pressure.

Problem #4:
Identical-Appearing Trucks May Have Very Different Towing Capacities
Here's another example of how actual tow capacities can be tricky to guarantee. A Dodge Dakota SLT Quad Cab 4x4 with a 5-foot bed, five-speed automatic, 545RFE automatic and the 4.7-liter V-8 engine with 3.92:1 axle ratio is rated to tow 6,850 pounds, and up to 11,700 pounds in gross combined weight. Yet the exact same truck, with 3.55:1 axle gears, will be rated to tow only 5,650 pounds, and 10,500 pounds total. Both trucks have the same axles, the same curb weight, the exact same equipment packages. But they have different gear ratios. Just altering one item on the spec sheet--an item you can't see--changes the ratings by 1,200 pounds of towing capacity.

What to do:
Your door sticker may not identify the gear set in your axle(s). Get under your truck and find the axle tag or housing stamp. Use that to compare with the info charted in your owner's manual.

Problem #5:
State Laws
The definition of "properly equipped" is also set by state law, which governs trailer length, weight, brake standards, width, height and towing speeds, among other things. You might talk with your trailer vendor to make sure you are in compliance when you buy your trailer. Problem is, even if you are within the laws of your home state, you might be a sitting duck the next state over.

As a general rule, the maximum trailer height is 13 feet, 6 inches, but 17 states do permit 14-foot height. One state, Nebraska, allows trailers to be 14 feet, 6 inches.

In most places the maximum trailer width is 8 feet, 6 inches, but in three states, it is 8 feet and in one state, Hawaii, it is OK to be 9 feet wide.

Maximum trailer length ranges anywhere from 40 feet (13 states) to 53 feet (5 states) and everywhere in between. In 12 states, there is no maximum length at all.

Maximum combined rig length varies from 85 feet in Wyoming to 55 feet in Maryland, and ranges widely in between.

Maximum towing speeds can be as high as 75 mph (8 states) or as low as 45mph, as in Alaska.

There seems to be no rhyme or reason to this patchwork of regulations. In California you are required to tow at 55 mph with trailer brakes on your 1,500-pound, 14-foot tall, eight-and-a-half-foot wide trailer, with 65 feet as your maximum overall length. When you get to Arizona, the same rig is illegally wide by six inches, illegally tall by six inches, but you can go 70 mph.

In Massachusetts, it is fine to tow a 40-foot trailer weighing 10,000 pounds at 65 mph without trailer brakes . . . but if you cross the border into Maine, and your trailer weighs 3,000 pounds, you better have trailer brakes. In Tennessee, trailer brakes are required if your trailer weighs 1,500 pounds, in Utah at 2,000, in Oklahoma at 3,000, in Delaware at 4,000, in Alaska at 5,000 pounds, and in Massachusetts, it's a truly optimistic 10,000 pounds.

What to Do:
You'll have to check the regulations in your state, and the states you might tow through. Just Google up "Towing Regulations" and you'll find any number of links that will chart out all the info you need. It may take a trip back to the trailer dealer to get set up to comply in neighboring states, but it might save you a couple of tickets, and keep your insurance company on your side if the worst should happen.

PhotosView Slideshow
Tongue load is difficult to measure accurately, but you can get a rough idea by noticing how level the tow vehicle sits. Here, we see a heavily loaded truck and trailer that appears to be well balanced, front to rear. To be more precise, measure the distance from wheel well to ground, before and after hooking up the trailer, to see how the trailer's weight alters the tow vehicle stance.

Problem #6:
Tongue Weight
Tongue weight is actually the hardest requirement to address, and one of the most important to get right. Too much tongue weight and you overload the rear axle, maybe blow a rear tire or melt down the axle gears. With the front end pointing to the sky, steering and braking will be sketchy. On the other hand, with too little tongue weight, the trailer will haul up on the rear axle of your truck, so you'll overload the front axle and front brakes, and have almost no rear brake effect at all. And the hitch could come off the ball with any bounce.

As a general rule, manufacturers specify that tongue weight be 10 to 15 percent of the total load. If your trailer weighs 6,000 pounds, tongue weight should be around 600 or maybe 750 pounds. This is too much to check using a bathroom scale, and difficult to accurately check at the truck scales.

What To Do:
Your most practical solution is to go by how level the tow vehicle sits. You can do this visually, or you can actually measure from the top of the wheelwells to the ground, loaded and unloaded. If you find the tow truck sitting at an unlevel attitude, move cargo around until the combination is leveled out. You want all the tires to be handling their part of the load. Otherwise, better hope braking and steering won't be necessary when that kid on a bicycle crosses the road in front of you.

Trailer tires are rated by miles, not by tread wear. Usually 5,000 miles is the limit, so they should be replaced even if the tire appears to have good tread, or whenever cracks appear on the sidewall. To reduce the tendency for sidewall cracking if your trailer sits during the week, make sure the trailer rests with tires at full pressure on level ground. For long-term storage, put the trailer on blocks, and reduce inflation pressure.

Problem #7:
Replacement Tires
Most of us have reason to add bigger wheels and/or tires to our tow rigs, and some of us have been known to run tire pressures at somewhat less than the maximum, for comfort and traction. Unfortunately, that compromises the factory tow ratings. Aftermarket wheels are generally not Department of Transportation (DOT) approved, and may not be perfectly matched to the tires you have chosen. Bigger tires, especially those with a more aggressive tread, almost always do not have the same load rating as the stock tires. When you try to tow with them, you have created a new weak link.

What To Do:
Before you tow on that set of new rubber, compare the load ratings versus the tire specified in your owner's manual. If your new tires can't carry the same load, reduce your towing/hauling weight accordingly. Be especially cautious when replacing dually tires, as there are not many combinations that keep the factory load ratings intact.

Check the sidewalls to see what the difference is, and do be certain you have the tire pressure maxed out to the number on the sidewall using that good tire gauge you always carry.

6 Safety Tips
1. Recheck All Straps And Tie-Downs
Keeping a load under control is kind of like securing a houseful of gear during a simultaneous earthquake and hurricane. Continuous vibration, bouncing, pulling and pushing tends to shift cargo with every bump, stop and start. The resulting load spikes will inevitably stretch tie-down straps and loosen the hardware holding everything tight. Meanwhile, the 60-mph windstorm going on outside is fraying ropes, and battering covers. Next thing you know, something is flapping in the wind, your load is unbalanced, and there is smoke pouring out of your rear axle. Get in the habit of retightening all straps and tie-downs at every fuel stop.

Under-inflated tires generate heat, and become prone to failure. It's essential that they be pressurized to the maximum psi shown on the sidewall, and that you use a reliable tire gauge to check it.

2. Be Fanatical About Tires
You can't be cautious enough about checking tire pressures, especially when towing on the highway where heat builds up quickly. All it takes is one blowout on a truck or trailer to ruin your weekend. We've heard of people using pyrometers to check tires at rest stops, to find out if any are building up heat. If one tire is hotter than the others, there is always a reason why.

3. Grease Check
If your trailer's tires are good, and the brake and signal lights are working right, you may still need to repack bearing grease. Bearings are a weak point in trailers, because the hubs get hot in a very short distance. In a boat trailer, when the wheels are submerged, the hubs suddenly cool, sucking in water and grit. On other types of trailers, especially if they are not used regularly, condensation moisture can seep into hot hubs as they cool, which causes rusting and lubricant failure. Bearing grease is usually colored-coded by temperature rating. The higher temperature greases cost more, so you can balance the type of grease you need against the amount you tow.

4. Don't Borrow Trailers
For starters, your buddy's tandem- or triple-axle trailer will turn a much wider arc and handle very differently from your single-axle trailer. Driving technique aside, the issues that arise when slapping on someone else's trailer include brake controller compatibility, hitch hardware compatibility, electrical compatibility, and all the usual concerns about maintenance, weight and balance. You may have carefully worked these out for your own truck and trailer. Change trailers, and you have to start all over again.

5. Do A Pre-Flight Walk-Around
Before you hook up and take off, just take one more look around for peace of mind. Check the tie-down straps one more time. Make sure the tow truck looks good, lug nuts tight, and the trailer safety chains are crossed, with enough slack so you can turn. Make sure the locking pin is in place on the tow ball lever, that the breakaway cable is plugged in. Wheel chocks stowed? Tongue load looks good? Tongue jack is raised and locked, so it can't drop down while you drive? OK then...drive with confidence.

6. Towing Is Easy...
...stopping is hard. With a boat or trailer behind you, stopping distances are exponentially increased, even with properly proportioned electric trailer brakes. The basic rule is to allow a following distance of about 4 seconds when towing, and 6 seconds if the road is wet or visibility is compromised. At 65 mph, that's as much a 576 feet, almost three football fields. Sounds like a lot, but if you don't believe it, take your truck and trailer out on a deserted road and try a few panic stops. Assuming you survive, you'll choose to give the next guy plenty of room.

Improving Towing Capability
If you find your truck is overmatched, it may not be practical to try to upgrade, but there are a few things you can do. By installing lower (numerically higher) gears, you may be able to get a maximum-rated load rolling without stressing the transmission, rear axle, and cooling system quite so much. But you will have to tow at lower cruising speeds because of it, and mileage may suffer. Or theoretically, you could swap in a new, much heavier, set of axles that would allow for a little more tongue weight and GVWR.

Unfortunately, swapping in a new axle will also add weight that will go against your Gross Combined Weight limitation, which will not change. Another tactic would be to add cooling power, which might include a bigger/better radiator, or if turbocharged, a high-performance intercooler. If you do not already have one, an oil cooler and/or transmission cooler would be a smart move regardless. The transmission, another limiting factor, can be beefed up with a billet torque converter, and re-programmed using a chip that allows you to lock up the torque converter on hills. With the transmission not hunting between gears so much, it will live longer. Unfortunately, all these things cost real money. By the time you add it all up, plus labor, it might just be better to trade in your old truck for one built to handle the load.

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