Long-Life Trailers
Spec'ing and maintaining trailers properly can save you money in the long run
Deborah Lockridge
Senior Editor
If you think about it, the true revenue-generating element of a tractor-trailer is the trailer. It's the trailer that carries the cargo, which in turn generates revenue. The tractor is merely the means to get the trailer from point A to point B. Smart fleet owners recognize that and are paying more attention to their trailers.
"In order for trucking companies to survive and prosper in a difficult environment, with increasing fuel costs, increasing trailer and truck equipment costs, they have to use their assets more efficiently," says Steve Zaborowski, senior vice president with XtraLease. One way to do that is to spec and maintain trailers so they last longer and are in the shop less.
Many fleets and trailer makers are moving toward a trailer that will last 10 years with minimal maintenance.
"We've watched the ownership of trailers extended out further and further as costs keep going higher and higher," says Rob Ehrlich, chief technology officer at Wabash National. He's the man Wabash put in charge of developing a trailer that will last 10 years with virtually no maintenance.
"Semi trailers certainly last longer than 10 years today, but the maintenance costs go up as they get older," Ehrlich said.
The first step in developing a program for longer trailer life is to understand your operation. How are your trailers being utilized? What kind of weights are they carrying? How damaging is the freight — and the loading/unloading process — on the trailer? How many miles do your trailers run in a year? What are the most common repairs? How long do you want to keep your trailers? How long do you actually keep them?
There comes a point where you're better off buying new equipment than spending increasing amounts of money keeping up your older ones. This is where it's important to keep track of your maintenance costs, says Ehrlich. "You'd be surprised at how many fleets don't really track [costs] that well," he says.
THE RIGHT TRAILER FOR THE JOB
The first step to a longer life trailer comes when you buy it.
Perhaps most importantly, the trailer must be spec'd for the job it is expected to do — and even for the unexpected.
"A fleet will spec their trailers for one type of service, then they get a contract for a different type of service," says Craig Bennett, senior vice president of sales and marketing at Utility Trailer. "You order a dry van trailer spec'd for general cargo, then you get a beverage contract, or coils of paper, or certain automotive hauls. A typical floor rating on a dry van would be 16,000 pounds, but these loads can put 18,000, 20,000, or 22,000 pounds into the floor of the trailer." Similarly, loads such as rolls of carpet or bulk potatoes — "bulge" loads — put horizontal loads into the walls of the trailer that it may not be designed for. Either way, the excessive stress will shorten the life of that trailer.
"There's a fatigue factor from the effects of carrying cargo, whether it be weight, or the loading and unloading procedure," says Charlie Wells, director of dealer development and dump trailer products at East Manufacturing. That's true whether it's a dump trailer hauling bulk commodities, a flatbed trailer carrying coiled steel, or a van being loaded and unloaded by forklift.
Trailer manufacturers offer a variety of options to deal with fatigue and damage, such as Wabash's DuraPlate trailers and Utility's new steel-lined, squeeze-riveted 4000DX. You can spec things like thicker plywood and closer-spaced crossmembers.
However, spec'ing trailers for long life and low maintenance must be balanced against other needs, such as weight and cost.
"You have to take into consideration what is it costing me up front, what might it cost me in revenue because it's going to weigh more and decrease payload potential," says Wells. "But will it give me less maintenance costs and downtime and maybe improve resale value?" he asks. "It's really a balancing act."
It's important that maintenance personnel have a say in the specs.
"I've heard over and over from maintenance people who wish they had some say in how the equipment was specified," says Adam Hill, engineering liaison manager at Great Dane. "But that can go the other way, too. You can get a maintenance guy who will spec equipment so he doesn't have to do any maintenance, but the cost is just impractical."
LONG-LIFE OPTIONS
"If a trailer is properly spec'd, the box — for the most part — does a fairly decent job," says Ehrlich. "The undercarriage is where a lot of the maintenance issues are."
There are a number of long-life and low-maintenance components available for spec'ing, including thicker brake linings, synthetic lubes in axles, permanently lubricated landing gear and LED lights.
Trailer manufacturers offer a number of options for long-life and reduced maintenance wheel-ends. Utility, for instance, offers a wheel-end package warranted for 60 months.
Synthetic lubes are increasingly being used in wheel-ends instead of the traditional oil-bath lubrication. You reduce the number of oil seal leaks, which cuts back on the number of thrown-away brake shoes. Plus, you don't have to look at the oil in the hub daily.
However, while high-tech greases and synthetic lubes might promise less maintenance, some claim an oil bath lube that can visually be checked is better.
"I've seen too much lack of maintenance on components people considered 'lubed for life' or 'maintenance free,' " says Darry Stuart with DWS Management, a fleet consulting service. "The industry was kind of sold that the synthetic semi-fluid products were fail-safe and maintenance free, but they're not. With an oil bath, you may have more seal leaks, but there's a telltale you can see when something goes wrong."
Lighting has traditionally been one of the biggest maintenance headaches on a trailer. Proponents say LEDs, or light-emitting diodes, have greatly reduced those headaches.
The big appeal of LEDs is that they are resistant to shock and vibration, which are prime reasons why traditional lamps fail. They also give off less heat. Because of these benefits, LEDs can last a lot longer than incandescent bulbs.
"You're looking at lights that are now maybe twice the price to three times the price, but last 10 times longer," says Jay Gillam, manager of the heavy duty division for Peterson Manufacturing.
The downside is, when damaged, they are more expensive to replace. And they're often a theft target.
"Although I'm buying them and I'm using them, I'm still not convinced that LEDs are the way to go, because of the cost," says Stuart. "The jury's still out as far as I'm concerned."
Truck-Lite says its new LED Mini-Marker Light can help address the issue of LED replacements due to damage. "We estimate that 40% of lighting costs are a result of physical damage," says Brad Van Riper, vice president of research and development at Truck-Lite.
Because the new light is small, Van Riper says, it is less prone to physical damage. "Often times, trailers are targets for tree limbs, particularly on the passenger side of the vehicle. If you have a big proud marker light fitted on your trailer, it ends up being the chin that leads into the punch of the tree limb."
PREVENTING DAMAGE
Lights aren't the only part of the trailer subject to damage. In fact, much of the expense of keeping a trailer running comes from repairing damage. You can help keep those costs down by spec'ing properly and repairing promptly.
"Buying Wabash DuraPlates, for example, is more expensive up front, rather than paying more per month in downtime and repairs on the other end," says Ross Decker, GE TIP Mobile Maintenance Service Product manager.
The floor is also a prime candidate for beefing up. "Once you have to go into major floor repairs, if you put a pencil to it, it will kill you," says Stuart. "If it's a reefer, it almost doesn't make sense to do it."
Another type of damage is corrosion, which has become more of a problem in recent years because of the anti-icing chemicals used on many highways.
"Part of the key to getting longevity is to keep contaminants from getting into moving parts where corrosion would cause a problem," Ehrlich says. "If it's sealed for life, one of the best way to prevent corrosion is to never let contaminants in."
Ask your trailer manufacturer what they're doing on their trailers to prevent corrosion, whether it's standard or an option. Utility, for instance, uses a sealer between nearly all the joints in the trailer to help prevent moisture penetration. Utility also coats the upper coupler assembly to protect it from water and chemicals kicked up as the trailer goes down the road.
"It's amazing how someone will spend a thousand dollars on graphics but not $150 on a stainless steel rear frame option," says Stuart.
When you do have damage, it's important to get it fixed promptly and correctly.
For instance, if the wall or floor of a refrigerated trailer is punctured, says Utility's Bennett, and it's not repaired right away, "moisture penetration will do irreparable damage in the foam cavity of the trailer." The moisture will reduce the insulating ability of the foam, make the trailer heavier, and deteriorate the foam itself.
"Any kind of cut to the bottom rail, hole in the roof, or a cut in the floor, you want to be sure to repair those things promptly," Bennett says. "If they're not repaired, those kind of damages can progress and can result in severe cost and damage by weakening the trailer. We've had occasions where people did not repair wood floors, and a forklift under load went right through the floor."
Quality of repair is just as important as the speed of the repair.
"A quality repair done to correct specifications is critical to maintaining that box for the life of the trailer," says GE TIP's Adam Giannetti, who created the company's trailer repair standards. "The entire trailer is a truss on wheels. Every piece of it contributes to the structural integrity of the trailer."
While one four-inch pop rivet patch with some caulk around it may be fine, "I can't have a trailer with 15 different four-inch pop rivet patches if I'm going to keep using it for 10 to 15 years. So we're going to invest in, say, a four-foot section repair instead," says GE Tip's Ross Decker.
If you have recurrent damage, seek out the cause.
Wabash's Ehrlich recently dealt with a fleet customer that was having problems with damage to its rollup doors. "When we looked at the source of the problem, we found something was coming through the door because it was not restrained on the inside of the trailer. The company should have been looking at why it was happening and trying to prevent it, instead of looking for a stronger door to withstand it."
OUT OF SIGHT, OUT OF MIND?
"Historically, the industry buys trailers, and the next time they look at them is when they're junking them, trading them or selling them," says Darry Stuart.
A good maintenance program balances being proactive and reactive, says GE TIP's Decker. "On the proactive side, we do four PMs on our trailers a year. That's the best thing in the world, because you catch things before they break."
On the reactive side, he says, good records are key. His company can track repair data for leasing and maintenance customers and learn what repairs are most frequent for a fleet. Once you know where your problem areas are, you can address preventing them.
The key to maintaining a trailer for long life is regular inspections, covering items such as wheel ends, brakes, lighting, floors and tires. Even if a trailer is spec'd with a bevy of "maintenance-free" components, "maintenance-free" does not mean "inspection-free."
"Maybe it's so obvious you need to say it, but those small dollars spent for preventive maintenance are an effort to avoid large costs in the future," says Great Dane's Hill.
Although a certain amount of wear is expected on items such as brakes and tires, they can last much longer if you're doing regular preventive maintenance.
"If the brakes are in adjustment, they're going to last longer, and you'll see less damage to the brake drum," Decker says. "A tire might lose three to seven pounds of pressure a month. If you check it once a year, the tire pressure will be much lower [and more likely to damage the tire] than if you check it four times a year."
In fact, tires are one of the most overlooked maintenance areas on the trailer, and one that can cost you — or save you — a bundle. Trailer tires that are underinflated by as little as 10% lose 16% of their usable life. If they are underinflated by 30%, they return less than half of their usable life.
Using a tire gauge to keep tabs on tire inflation is a must. Make sure gauges are accurate with a calibrated master tire gauge. If you have problems maintaining an effective tire inflation program, you might want to consider an automated tire inflation system. (See Tire Talk on page 98.)
Wheel-end leaks are another area where regular inspection pays off. "A leak is something a mechanic can go in pretty quickly and correct," says Decker. "But if you don't notice that leak, pretty soon it leaks enough that you've got metal-to-metal contact, and much more expensive components can start to fail on your trailer. It may cost you $15, $20 to fix a leaking seal, but if you end up running that axle dry, it could be $1,500."
Regular inspections should also include lubrication. "There are some components that should be periodically greased, and I think that would be the first and foremost thing anyone with half a brain would do," says East's Wells. "But we find that lubrication is a problem in a lot of cases."
Utility's Bennett says many fleets don't re-grease electrical connections as recommended by the manufacturer. "That grease does dry out, and then the moisture penetrates the electrical system and starts to decay."
"There are a few areas that a good many companies tend to overlook," says Great Dane's Hill. "One of those is coatings or undercoating. Undercoatings are a maintainable item, and many people think they aren't." Sealants and caulking and door seals are other often-overlooked items you should inspect regularly.
Antilock brakes are another problem area. "We still find a lot of people who don't know how the ABS system is supposed to work, much less perform any maintenance on it," says Wells. Don't rely on the ABS warning light to let you know if there are problems. "Guess what happens — a lot of times the driver just disconnects the warning light," he says. "Or the light itself might be burned out."
How often should you inspect? That depends on your operation. GE TIP does four a year. If your drivers do quality pretrip inspections, perhaps two a year would work for your operation. The right amount of maintenance for a trailer used locally for delivery is going to be different from one going cross-country. If you're running three trailers per tractor and it's not that big a deal if one needs to be out of service for a while for repairs, you might not be quite as stringent about frequent inspections as someone who is running 1.5 trailers per tractor or someone who has an on-time money-back guarantee.
If you don't put consistent mileage on your trailers, it may be advantageous to use a mileage-based system of maintenance scheduling rather than a time-based one.
"Many fleets seem to be scheduling maintenance based on time, i.e., every X months," says Kara Bolster, marketing manager at Stemco. "In that case, some of the equipment may be overdue for maintenance, and some may not need it based on the usage of the trailer."
You can use a hubometer to keep track of the trailer mileage. Stemco offers an easier option with its electronic DataTrac, which has a trip feature in addition to a much larger display than typical hubometers.
"Many customers moved away from using mileage-based PM programs because they had to have a person keep track of the mileage," Bolster says. "With DataTrac's trip feature, they no longer have to have a person that has to keep up with the math."
Trailer Innovations continued...
