Blood Sweat and Gears: 12 Things You Should Know about Oil and Coolant Analysis

By Deborah Lockridge

Oil and coolant are like your blood and your sweat, says Dave Tingey, senior data analyst with Polaris Laboratories.They have to work together to keep you alive. “If your body is sweating while you’re running, you’re healthy,” he explains. “If you stop sweating, your blood is going to heat up, and you’re going to die. If your coolant doesn’t do its job, it’s going to oxidize that oil prematurely, and next thing you know, your vehicle’s going to die.”

Like your body, your engine fluids should have regular tests to check on their health. Here are 12 things you should know about today’s oil and coolant analysis.

1. It’s not your granddaddy’s engine anymore.

New engines, new fuels and new coolants have affected various aspects of fluid analysis. “With the constant reformulation of your coolants and your oils, the constant upgrading and redesign of your engines to meet emissions specifications, the loads put on oil have to be understood, and you have to realize how to best manage that piece of equipment,” says Tingey. “Oil and coolant analysis give you the ability to do that.”

Elizabeth Nelson, coolant program manager at Polaris Laboratories, also notes that today’s cooling systems have higher temperatures, higher coolant flow rates and higher pressures. “There’s a lot more going on than back in the ’70s because of the evolution of that engine.”

One area of significant concern is coolant leaks in oil over the past few years. With exhaust gas recirculation coolers a feature on new trucks since 2007, labs and fleets also have reported a frustratingly high number of EGR cooler leaks. In fact, according to
Mark Betner, heavy-duty lubricants manager with Citgo, 50 percent of premature lube-related engine failures in on-highway trucks are related to coolant contamination.

Oil analysis can help catch coolant contamination in the oil before you see significant engine damage, and coolant analysis can help detect something wrong with the cooling system.

2. There have been advancements in testing.

For instance, the advent of ultra-low-sulfur diesel (ULSD) has required a change in the way labs look for fuel dilution in the oil. Without as much sulfur, Polaris has switched to gas chromatography to measure the amount of raw fuel in the oil. ULSD also has affected the importance of measuring TBN—total base number, a measure of the acid neutralizing capacity of oil. Says Stede Granger, OEM technical services manager with Shell Lubricants, “With the use of ULSD, we don’t generate sulfuric acid in the crankcase anymore. There are other acids that form, but they are not as hard. So the focus on TBN just doesn’t have to be what it was before.”

Another advancement in testing, says Peter Thompson, director of marketing for Valvoline, is microscopic particle examination. “It really gives detailed information on different wear particles,” he explains.

Chuck Hamilton with CHS notes that ferrous metal (iron) content testing has become available at many used oil analysis labs, using a Particle Quantification Index (PQI). This test will pick up the presence of larger iron particles, such as a gear tooth or slivers.

3. Oil analysis can prevent premature wear and catastrophic failure.

With oil analysis, “You can see problems that are coming down the line with the engine,” says Henry Neicamp, field services manager for Polaris Laboratories. “So you can correct that situation instead of waiting till the engine has a failure. It doesn’t cost that much to do oil sample analysis, but the cost avoidance is significant as opposed to a significant engine repair and its resultant loss of productivity and downtime.” Shell’s Granger says with oil analysis, “you can actually see if you’re starting to inhale dirt into the combustion chamber, because you see that in the crankcase in elevated silicates."

Because oil analysis can alert you to situations where the oil’s no longer protecting the engine as it should, it’s a must if you want to extend your oil drain intervals beyond the standard recommended by your engine maker.

4. Coolant analysis is more than checking additive levels.

It’s not just oil analysis that can help catch damaging problems early. Traditionally, coolant testing in the field has focused on additive levels and whether there’s the right concentration of coolant vs. water. But coolant testing can do much more. People tend to put coolant in and forget it, but there are mechanical things that take place in the cooling system that will destroy that coolant, and the coolant in turn will attack the metals in the engine.

Laboratory testing can catch cooling system problems early, such as combustion gas leaks, electrical ground problems, localized overheating issues and air leaks.

For instance, Nelson says, pH levels can not only tell you if someone mixed a conventional fluid with an extended-life organic additive coolant, but also whether there is a chemical reaction taking place in the cooling system. Glycol, the foundation ingredient of coolants, can break down in excessive heat, forming degradation acids, and that can cause severe ­pitting in the cooling system. And that can come from something simple like a defective pressure cap, or corrosion and dirt plugging up cooling system passages. Polaris Laboratories recommends twice a year, before summer and before winter.

5. More coolants mean more potential for mix-ups.

Increasingly popular extended-life coolants are based on organic additive technology, which doesn’t work the same as traditional coolants. Some­times even different brands of extended-life technology don’t play well together.

As Shell’s Granger explains, “We do not recommend mixing, because your corrosion protection could significantly suffer. The additives in the [traditional] silicate product protect against corrosion in a much different manner than an extended-life coolant. When you mix the two, you may end up without enough of either type of additive to protect against corrosion.”

There are some test kits out there. Shell, for instance, just introduced a new coolant contamination test tool for its Rotella extended-life coolants and other leading brands, which uses two vials and three simple color indications. Its purpose is to make sure traditional coolant has not been mixed in with the ELC. But don’t automatically assume that a test that works for one brand of extended life coolant will work for another.

In addition, there’s a new “waterless” coolant on the scene. Evans coolant, because it’s made with glycols undiluted by water, boils at a higher temperature than regular coolant, allowing for reduced fanon time and fuel savings, according to the company.

This also means a very different additive package—without water, non-corrosive additives aren’t required, for instance. So for this coolant, the biggest thing to test for is the accidental addition of water.

6. Alternative fuels can change things.

If you’re running alternative fuels, fluid analysis may be even more important — and you’ll need to check with your lab or supplier about special tests to run. When using a biodiesel blend in your engines, you need to keep an extra-close eye on fuel ­dilution in your oil. Natural-gas engines may run hotter than comparable diesels, and compressed natural gas may cause nitration in the oil.

7. Test results are easier to understand than before.

Once upon a time, you mailed off an oil or coolant sample and it took weeks to get the results back in the mail — and then all too often it was a confusing mishmash that it seemed you needed to be both a mathematician and chemist to understand.

Today, however, the information is transmitted electronically. “Instead of reading the old paper reports, more and more companies are utilizing software and better electronic delivery methods from used oil labs to receive quicker data and help them better manage their maintenance programs,” explains Len Badal, commercial sector manager, Chevron Lubricants.

With most programs, you can pull up the results via a website and analyze individual vehicles, slice and dice by make of engine or other parameters.

8. Be careful when switching analysis.

Different laboratories may test for different contaminants and chemicals in different ways. So if you switch oil-analysis providers, the results may not be comparable. Tingey explains that you can see if the old lab and the new lab are using the same testing method by looking at what ASTM method they’re following. For instance, he says, some labs may test for fuel dilution using FTIR, which has a ­certain ASTM method associated with it, while Polaris Laboratories uses gas chromatography, which is a different ASTM method.

Another thing to look for when choosing a lab is whether they are ISO17025:2005 accredited. (This is an international standard for calibration and testing laboratories.)

9. It won’t do any good if you don’t do it right.

You need to establish a trend, a fingerprint, for each particular engine. That way, when you get a marked departure in wear rates or oil condition trends, you’ll have something to compare the data to.

Keep in mind that results can vary by engine manufacturer, engine type, oil capacity, whether there’s a bypass oil filtration system, etc. Valvoline’s Thompson says the first thing a fleet should do is work with their oil supplier or lab to figure out what the sample schedule should be, which will vary based on the compartments you’re sampling (engine oil, coolant axles). You need to identify the sample points you’re going to use, and use the same sample point each time.

Take care when taking samples to avoid contamination—don’t just grab any jar that happens to be lying around—and make sure the machine is at normal operating temperature.

10. You can’t file away the reports.

The key to making fluid analysis worthwhile is twofold: One; understanding the results and two, acting on them. Polaris Laboratories’ Neicamp says too many maintenance managers just print out fluid-analysis reports and put them in a filing cabinet. You need to work with a lab that will help you understand your results. “The key value derives from establishing what the fleet wants to measure, along with establishing it as part of their maintenance program,” says Chevron’s Badal.

11. There are more ways fluid analysis can help.

There are some other benefits oil and coolant analysis can offer:

  • Increase resale value by being able to provide complete fluid analysis history.
  • Prove to yourself the value of premium-quality oils.
  • Use it as a tool to measure maintenance quality at different shop locations.
  • Use it as a tool to compare equipment to help in future purchase decisions.

12. Analysis is not enough.

All too often, truck owners give up on oil analysis because it didn’t show ­anything wrong, and the engine failed the next day. Oil analysis is just one tool — it can’t show you everything that can go wrong in your engine. The same, of course, goes for coolant analysis. Nevertheless, it’s important. “We have done a lot of different stuff with engine oil,” says Steph Sabo, of Nashville’s Norrenbern’s Truck Service, “from testing different oils to running bypass oil filtration. The one thing I have really learned is that engine oil is like a person’s blood. You better keep it clean, or the body shuts down. We have shut down some engines from ‘bad blood’… and that’s real expensive.”

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