Bill Nicholson uses a specialty oil to extend the life of his Cummins engine.

David Wadsworth is a long-haul trucker, so it’s a little unusual for him to be home on a weekday. Even odder is that he’s sidelined with a mechanical problem.

“My transmission’s down today,” says the owner-operator from Lolo, Mont. Wadsworth is waiting to find out whether he has to have it rebuilt. Another driver might be more downcast about the blown tranny, but Wadsworth figures he’s due some mechanical grief – his Caterpillar engine has traveled nearly 1.4 million miles, and it’s never been overhauled.

Manufacturers have talked about building million-mile trucks for years, but few engines achieve that status. Plenty make it to 800,000 or 900,000 miles, but by then bearings, seals, injectors and linings usually have worn out, and the engine is due for an in-frame overhaul.

What sets apart the engines that do make a million? Frequent and thorough preventive maintenance, proper spec’ing and smart operating habits, according to the million-mile engine owners Overdrive spoke with.

“Fix the little things before they become big things,” Wadsworth says of his secret to prolonging his engine’s life.

The head of the largest truck breakdown service in the country agrees. “Over the years the truck and engine makers have done a tremendous job building longevity in the major components of trucks and the ancillary components,” says Oren Summer, president and CEO of FleetNet America. “Just doing routine maintenance will keep a truck running for a long time. Give it a little more attention – in the driving and in the maintenance – and the engine will go forever.”

Million-mile engine owners change their oil frequently – often more frequently than the oil demands or than engine makers recommend. They also pay close attention to other systems when the hood is up or the truck is over a pit.

“You have to stay on top of maintenance,” says Ryan Rees of Dunkirk, Ind. He and his wife, Lynn, are owner-operators with FedEx Custom Critical. Their Kenworth T600 expediter has a Detroit Diesel Series 60 that should trip the million-mile mark this year. Ryan Rees religiously changes the oil and the fuel, water and oil filters every 10,000 miles, if not earlier.

“I don’t always go for manufacturer’s specs on things,” he says. “I deal with a lot of city traffic. I’m in and out of New York City, Chicago and Atlanta a lot. You’ve got to look at that. Some days I’ll be in areas where I’m always at a low idle speed, and I’m in stop-and-go traffic.”

Others change their oil at longer intervals but rely on either higher-grade oils or additional systems to improve oil quality. Jody Farris of Coldwater, Mich., owns two trucks with million-mile Detroit Diesel engines. He changes the oil in the truck with the highest mileage every 20,000 miles, a relatively long interval for many owner-operators. But Farris says he’s added an oil filtration system with an additional oil filter, and a bypass keeps his oil cleaner longer. “I haven’t had any trouble with the engine,” he says. “It’s unbelievable. It runs all over the country.”

Cummins N14 owner Bill Nicholson says the right oil has a lot to do with his engine’s 1.2 million miles. The coal hauler from Wheatland, Ind., keeps his latest oil analysis handy and has become a salesman for the company he buys his oil from, the Texas Refinery Corp.

Nicholson says his oil costs a lot more than conventional oil – $13 a gallon compared with $7 to $8. The oil is a group II, non-synthetic oil similar to lubricants made by the major oil companies. But it has a special additive package designed to minimize varnish, gum and sludge and to resist breakdown at high temperatures, according to the company. That extra protection is worth the money, Nicholson says. So are frequent filter changes. “Every 20,000 miles, I change the oil, water and fuel filters.”

Pick an oil from a major manufacturer and stick with it, FleetNet’s Summer advises. That’s true for filters, too. “Major companies make good filters, and they make good media for them,” Summer says. “Those filters have been through the proper engineering and testing. There are some off-brands that are bargains. But you’re not buying a bargain, but a liability.”

Cat owner Wadsworth is particular about his oil. Hundreds of thousands of miles ago, the owner-operator added a centrifuge-type oil filter to his Cat 3406B/PEEC engine, which now has 1.3 million miles on it. The result: “My oil has a lot less soot and grit in it,” Wadsworth says.

He also added a fuel preparator, which removes air from diesel and pressurizes it before it’s injected in the engine. Wadsworth says the fuel device makes the engine burn cleaner, which in turn dumps less pollutants into his oil. “I’m burning pure fuel,” he says. “The better the burn, the cleaner the burn.”

Alabama trucker Max Middleswart and his brother likewise added a bypass oil filter and a fuel preparator to their Kenworth T600 with a 3406 Cat. Switching to synthetic oil early helped get 1.2 million miles out of the 1995 truck, as well as “PM, PM, PM, PM and more PM,” he says.

“Change your oil religiously,” Middleswart says. “Change your tranny and rear end oil every 200,000 miles, and fix all little things before they become big things. Grease and grease guns are very cheap. Use them a lot.”

Oil may be key, but other systems need regular attention, too. “The cooling system is as important as the oil, especially on more recent engines,” says FleetNet’s Summer. “Temperatures in today’s engines are so much hotter than they used to be.”

Rees flushes his cooling system at least once a year. The coolant may not always need to be replaced, but the PM helps spot leaks and catch problems with the coolant that could lead to engine failure. “My mechanic’s shop is aggressive,” Rees says. “If they see a fluid that isn’t right, they let us know. They notice problems before we notice them, and they fix it.”

Summer says few owner-operators and carriers actually follow a schedule for their coolant changes, even though manufacturers recommend it, because coolant is expensive. Instead, they test and add supplemental coolant additive packages, which are fine as long as the packages are added before the chemicals in the coolant become depleted. The point, Summer says, is that truckers need to keep an eye on not just the coolant level but its quality.

Frequent PM for specific systems also helps alert you to other problems that might go unrecognized. “If you’re putting your hands on the hoses regularly, you don’t have a problem blowing a hose and overheating,” Wadsworth says. “You know you have that problem solved.”

A driver’s training and behavior also play a big role in engine life. “The way he changes the gears, the way he stops, the way he starts impact not just engine longevity but the whole drivetrain,” Summer says. High idle times at low idle rpm also do a lot of damage.

Wadsworth says he drives his Cat with care. “I use cruise control an awful lot. I don’t lug it down. I shift when it needs to be shifted. I drive like I’ve got eggs under the throttle.”

But truckers don’t have to pamper their trucks to achieve longevity. “I pull 80,000-pound loads with it every day,” coal hauler Nicholson says of his Cummins N14. Still, he takes it easy on rough roads when he’s coming out of the mines.

Low idle times also help keep engines youthful. Many engines that never make a million miles on the odometer nevertheless have many more hours on the engine than most owners suspect. An hour gauge, which is not part of the usual dashboard package on over-the-road trucks, can be helpful in telling drivers how many “miles” an engine might have on it. If an owner-operator averages 60 mph and 100,000 actual miles a year with 40 percent idle time, the engine has operated the equivalent of 166,667 miles. Idle hours are usually less efficient and more hostile to engines than highway miles, so an engine that has relatively few miles on the odometer may be more worn out than it looks if it’s been idled a lot.

“You have to try and have as little idle time as possible,” Wadsworth says. “If it’s really cold out, bump up the idle so that the engine really heats the oil, and the oil lubricates right. Oil doesn’t lubricate as well when the engine isn’t hot.”

An idling engine tends to build up carbon, which shellacs components running in oil. This may not be a big problem in modern engines, which tend to run hotter, but it can be in older engines – especially ones that lack idle stops or adjustments. “At idle, you’re not really doing a great lubrication job, either,” Summer says. “It’s an adequate job, but not a great job.”

Other problems can arise when a multi-unit owner-operator employs drivers for his other trucks and those drivers change from day to day. PMs can be missed and different driving styles can wreck the driveline. Indicators of engine failure – such as unusual sounds and smells – can be overlooked because drivers aren’t familiar with the equipment they drive.

Bill Watkins, president of Rapid Delivery, has a Volvo day cab with a million-mile D12 engine. It has bucked convention, he says, because the truck’s two drivers are always the same, and they notice minor problems before they become major ones. Trucks that operate locally tend to get the harsh mileage of city driving. This truck, though, has the advantage of returning to the company’s Jackson, Miss., yard every day and receiving repairs that would have been delayed in an over-the-road application. “If anything goes wrong with that truck, it gets taken care of,” Watkins says.

Owner-operators have an advantage, Summer says. “Owner-operators will squeeze more out of the lemon than most carriers. They apply more attention to what they hear, smell and see because it’s their vehicle.”

Some engines die young because they aren’t spec’d properly for the job they end up doing.

Owner-operators Ryan and Lynn Rees made a point of avoiding that problem by spec’ing their expediter with a 500-hp engine – even though the 10-wheel truck weighs only 30,000 pounds empty, and loads are often light. “Bigger horsepower engines last longer, stay stronger,” Ryan Rees says.

Although not everyone agrees with that philosophy, spec’ing an engine so that it can perform its most difficult application easily is essential. A smaller engine may strain under heavy loads, adding extra stress that could lead to engine failure.

When the Reeses operated engines at about 300 hp to 330 hp, they were unable to maintain speed on hills or even keep up with traffic with heavier loads. At 939,000 miles, the couple’s Kenworth T600 with a Detroit Diesel Series 60 will likely reach the million-mile mark this year – and the way it’s running, Ryan Rees says, it could go 1.5 million.

“It doesn’t take off like a striped cat out of the gate,” Rees says. “But once you get to seventh or eighth gear, boy, she purrs. It’s set up for a smooth, steady cruise down the interstate – for distance and for the kind of power necessary to get up and down hills.”

Plenty of lower-horsepower engines, however, have crossed the million-mile mark just fine. When Summer led the breakdown department of Carolina Freight Carriers, the company routinely saw 325-hp engines roll over 1 million miles. The engines that did it were spec’d for the job, well-maintained and piloted by good drivers.

“Fifteen years ago, we were running our trucks LTL, slip-seat operation for a million miles,” Summer says. “It all goes back to the engineering history of the engine. Given a quality product, a quality driver, personal attention from driving the vehicle and maintaining it, most engines will go a million miles. There’s no luck involved.”

Farris would disagree.

“I really don’t know why it’s still running,” he says of his engine. “I’ve been a big Detroit Diesel fan my entire life, but there seems to be no rhyme or reason for it. I guess it’s luck.”

In the end, no single reason gets an engine to a million miles. But proper driving technique, smart spec’ing and tender loving care in the form of frequent PM help extend the life of any engine. Taking care keeps owner-operators in business and prevents breakdowns that could be catastrophic.

The old adage about equipment is true, owners say: If you take care of your truck – and its engine – it will take care of you.

Most truckers operating million-mile engines enjoy one big financial benefit: no truck payment.

Owner-operators will often trade or sell an older truck, fearing potentially large repair expenses will hurt the bottom line. But there’s money to be made if you can push your engine and truck past a million miles.

“When we bought our truck I hoped we could make the last payment before I had to put another engine in it,” says 25-year owner-operator Jody Farris. “That was four years ago.”

Assume you buy a new truck on a five-year loan and drive it 120,000 miles a year. When it’s paid off, it will have 600,000 miles. Run it another 40 months and you’ll reach 1 million miles. If your monthly payment was $2,000, you’ll save $80,000 in payments during that period. Granted, you’ll have more repairs and downtime than you’d have with a new model, and you’ll have no depreciation to reduce your tax bill, but you’ll likely come out ahead financially.

Owner-operator David Wadsworth says that many truckers give up too easily on maintaining aging trucks. “Because the vehicle is getting older, they become less concerned with repairing it. They’re less concerned about a seep at the water pump. They’re less concerned about low voltage.”

As a result, the truck’s brief lifespan becomes a self-fulfilling prophecy. The engine develops problems until the driver is forced to trade for a newer model – and a new round of truck payments.

Just because they have more than a million miles on their trucks doesn’t mean these owners haven’t had their share of repairs. Most have replaced alternators, starters, water pumps and the like. Some have opened the bottoms of the engines for inspections, others the top for cleaning.

But these faithful workhorses still have their bearings, shafts, pistons and linings intact. David Wadsworth tried to have his engine rebuilt at 1.3 million miles, but his Caterpillar dealer told him he didn’t need it. Instead, he had the engine turned up and added new injectors and new turbos.

Detroit Diesel owner Jody Farris added a new water pump, diamond seal and rods, but hasn’t done much else. Expediter Ryan Rees says he once changed an alternator in the Alaskan wilderness, but his engine is pristine.

Cummins N14 devotee Bill Nicholson has replaced his starter (at 1 million miles), a camshaft and a turbo. But his pistons have never been out, and he didn’t touch his fuel injectors until he reached 1.2 million miles.

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