Corey Taylor, senior heavy-duty tech support technologist at BP Lubricants, has some advice on what NOT to do:
"There are many ways to cut corners, but the most common involve drain interval extension with cheap oil and no used oil analysis, cheap quality oil and filters, and even changing oil but not filters or vice versa," Taylor says. "All of these strategies can be costly in the long run, because they compromise the performance and protection of critical engine parts. Premature replacement of failed engine parts or catastrophic engine failure is far more costly than any money you would save in the short term with cheap lubricants."
Saving up front
Of course, the most obvious thing to do would seem to be to buy less expensive oil.
If you go this route, it's important to make sure you're getting oil that meets API (American Petroleum Institute) testing standards required for your engine. Most 2007 and later engines require API CJ-4, for instance, to protect the diesel particulate filter. Some engine makers also have their own oil specs.
Reputable brands tend to have "tiers" of oil quality and price available, offering both a premium product and a "fleet oil" or a "mainline" oil that meets the basic specs but doesn't offer some of the enhanced properties of the premium brand. Depending on your operation, one of these "fleet oil," lower-priced tier oils may be the right fit.
But be careful when shopping around for a deal on engine oil.
"There's a lot of private labeled diesel engine oil out there that really a lot of times is very low price," cautions Andy Arendt, director of lubricants marketing for CHS, which sells Cenex brand oils. "I think like a lot of other things: If it sounds too good to be true, it probably is."
Arendt says when buying any oil, the first thing to do is make sure the oil has the proper API license for your equipment.
Next, he says, ask the vendor about the composition of the base stock, and get additional information on the oil's performance characteristics specific to soot handling, wear protection, acid neutralization, capacity for extended drains, etc.
"There's a lot of people trying to sell a lot of low-priced oil out there, and sometimes the actual product can be a little bit dubious," Arendt explains. "Particularly if you're buying in bulk, get it in writing that it meets the API standard."
Even if you get a quality oil that is API licensed and meets your engine manufacturer's requirements, by buying oil that costs less up front, you could be sacrificing potential cost savings down the road, in areas such as extended drain intervals, better fuel efficiency, and longer-lived equipment.
The case for premium oil
Lubricant companies offer premium formulations that go well beyond the API standards and provide long-term benefits that could more than pay for the additional up-front cost.
"When you buy a cheaper oil, you may save a few dollars on the initial oil change, but there may be issues with deposits and soot control that create enhanced wear," cautions Joe Huang, senior engineer with Ashland Inc., which makes Valvoline and Cummins-branded oils. "Instead of getting the 700,000 or a million miles out of the engine you would expect, you may find you have to do a rebuild at 500,000 miles. And when you look at the cost of downtime of a truck that suddenly starts having oil pressure problems, that's a lot of money. Buying a higher-quality oil is relatively cheap insurance against future problems."
Mark Betner, heavy-duty lubricant manager for Citgo Petroleum, points out that lubricants only make up 1 percent to 2 percent of a fleet's variable operating budget. You might save $50 per year per truck by shopping around for cheaper engine oil, he says. But you might be able to save $500 to $1,000 dollars per year per power unit by optimizing the service interval.
He explains: If it costs $150 per truck to change the oil and you're doing it at 25,000-mile intervals, a 100-truck fleet spends $15,000 to change the oil in all those vehicles. If you do that five times a year (figuring 125,000 miles per power unit), you spend $75,000 in oil changes.
If you can double that oil drain interval to 50,000 miles - and Betner says he has many customers that are doing this safely - you've saved $35,000 to $40,000 in oil changes in that 100-truck fleet. That's more than enough to make up for the cost of a higher-quality oil and an oil analysis program and still have money left over.
"But if you shopped for the better deal on the oil, if you use the second level of that brand, [that 100-truck fleet] would save $3,500," Betner says. "You lost a 10 to one savings opportunity [compared to] if you had pursued the possibility of an extended drain strategy" instead of just buying less expensive oil up front.
As Betner lays out, extending the oil drain intervals in your fleet, if done properly, can save you money in terms of less oil and fewer filters used, less labor, and less downtime, allowing the truck to stay moving and making money on the road.
"We have always felt that extended drains are the best way to cut your fluid costs," says Joe Huang with Valvoline, noting that a premium filter works in conjunction with the oil to accomplish this.
But there are a few things to keep in mind. You need to choose an oil that is formulated to allow extended drains, you need to do used-oil analysis, and you need to coordinate your other PM intervals.
If you're looking to extend oil drain intervals, consider CJ-4 oils over the CI-4 Plus, even if you don't need them for any 2007-emissions engines. These were designed with a more robust additive package, with very different chemistry from previous formulations.
"We have demonstrated that the CJ-4 lubricants, especially the premium CJ-4 technologies, have the value built into them, for extending oil drains," says Reginald Dias, director of commercial products for ConocoPhillips Lubricants.
Don't forget about lubrication on the rest of the truck. You may need to also look at choosing chassis and fifth wheel lubrication products that allow you to extend those intervals to equal to what you're doing with the engine oil. They go hand in hand. "Many fleets have told me, it can be a weak link," Betner says. If you get a lack of lubrication in those critical chassis components, repairs could cost you all the money you've saved on longer drain intervals.
Used-oil analysis is a must for extending drain intervals and, in fact, can be a good idea to add to your preventive maintenance program even if you aren't.
"Oil analysis is almost like doing blood analysis to get insight into one's health," Dias explains. "Oil analysis tells a good deal about the health of the equipment. The condition of the oil can give a clue as to how the engine is operating. Not just wear; there is fuel dilution that can take place, coolant leaks, dirt contamination. All are detrimental to the performance of the engine." And all can be detected through used-oil analysis.
"The engine manufacturers say you won't violate your warranty" by carefully extending your drain intervals, Citgo's Betner says. "But [they say], we want you to have a support system with oil analysis that gives you a good bill of health, and we want you to have impeccable maintenance records, so if there ever were a dispute over warranty you would have backup for what you did and we would know you didn't just extend your drains by flying in the dark."
Extending oil drain intervals is a cost-saving strategy that's been around for years. A newer strategy is choosing lubricants that can help improve fuel mileage. When fuel prices are high, the cost savings more th