How to Do an Engine Oil Analysis

Metal shavings from engine parts, foreign debris, and oil that doesn't lubricate properly can all contribute to eating up an engine.
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One of the worst pieces of news you can ever receive as a car owner is to hear that your engine is toast -- so worn down that your only options are to replace it or buy a new car.

Metal shavings from engine parts, foreign debris, and oil that doesn't lubricate properly can all contribute to eating up an engine. Replacing one isn't a cheap proposition -- depending on your vehicle, you're looking at a few thousand dollars (at least) for parts and labor. Even if just certain parts of the engine are worn down, like the engine bearings for example, repairs could require big bucks.

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Of course you knew that your vehicle engine's oil plays a crucial role in keeping your car, truck or SUV running smoothly. But did you know that the condition of engine oil can actually provide clues to an engine's health -- sort of like a blood test in humans?

It can, and it's actually pretty easy to have an engine oil analysis done for your vehicle. You can even purchase kits that allow you to provide a sample of oil, analyze the results on the spot, or have the results mailed back to you from the lab.

This article will cover a few things about engine oil analysis:

  • What's involved with performing an engine oil analysis
  • Several ways that oil analysis can save you money
  • How oil analysis can keep your four-wheeled (or two-wheeled) chariot on the road longer

Go to the next page to learn what goes into an engine oil analysis kit ... and what you'll get out of using one.

Engine Oil Analysis Kits

The oil analysis results will let you know if the oil is excessively contaminated with fuel, water or antifreeze, all of which reduce the oil's ability to lubricate your engine effectively.
The oil analysis results will let you know if the oil is excessively contaminated with fuel, water or antifreeze, all of which reduce the oil's ability to lubricate your engine effectively.
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You have two options for analyzing your motor oil with a kit. You can buy one that lets you interpret the results for yourself, or you can purchase the services of a professional laboratory, such as Blackstone Labs or Oil Analyzers, Inc., just two of the leading firms out of many that offer oil analysis.

Either way, kits typically cost less than $30, and sampling your oil is relatively easy. Or at least, it can be. There's the somewhat messy sampling method, of removing the oil filter and catching a sample of oil (enough to fill the small container for the kit). Or you can do it the no-mess way: use a vacuum pump to siphon oil from the dipstick tube or crankcase filler hole. Such pumps are available at auto supply stores, or often, from the providers of the analysis kits.

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So what's actually in the kit? If it's one that you mail in, it will likely include a small jar or bottle for the sample, along with a label you fill out that tells the lab about the sample. It may also include a separate container into which you can pack the sample for mailing. You then receive the results by mail, e-mail or phone, typically within a few days.

For tests that let you read the results at home, (like QMI of Missouri's MotorAnalyzer), you just place a drop of warm motor oil on the supplied test sheets. Then you compare the pattern produced by the oil drop with the patterns shown on the included test analysis guide. The pattern of colored concentric rings gives you insights as to:

  • How efficiently your fuel is being burned
  • How much life remains in the motor oil
  • Whether there's water, fuel or other contaminants in the oil

If you're a novice, especially, it can be pretty intimidating trying to interpret what those results mean. Click to the next page to learn more about interpreting the results of an engine oil analysis.

Interpreting Oil Analysis Results

You can buy an oil analysis kit that lets you interpret the results for yourself, or you can purchase the services of a professional laboratory that will analyze the results for you.
You can buy an oil analysis kit that lets you interpret the results for yourself, or you can purchase the services of a professional laboratory that will analyze the results for you.
Monty Rakusen/Getty Images

So just what, exactly, will all this information about your engine's oil tell you? And what will that do for you?

If you send your oil sample to a lab for analysis, technicians will check for lots of things, including the presence of metals and other elements, such as aluminum, chromium, iron, copper, lead, calcium and more. If certain materials are abnormally high in your oil, it could point to excessive wear in a certain engine part.

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The analysis also lets you know the oil's viscosity, compared to what it should be. The Total Base Number (TBN), which lets you know how much of the additives -- chemicals that enhance the oil's effectiveness -- remain.

Having this knowledge beforehand could save you lots of money and aggravation, as it gives you time to catch problems before they result in a catastrophic failure on your vehicle (like an engine seizing up).

The results also let you know if the oil is excessively contaminated with fuel, water or antifreeze, all of which reduce the oil's ability to lubricate your engine effectively.

But there are at least two more ways an engine oil analysis can save you money.

If you're considering buying a used vehicle, a car, a truck, a motorcycle or even a piece of diesel construction equipment can be quickly given the oil analysis test to see what kind of shape they're really in, beneath their flawlessly washed and waxed exteriors. An engine oil analysis can give you a look deep inside the workings of the engine without you having to take it apart. Naturally, a lab report that comes back showing lots of metal particles may be a sign that you should avoid taking that vehicle home.

Another potential money saver is if the analysis shows you can extend the interval between your oil changes. The recommendation used to be that you change your oil every 3,000 miles (4,828 kilometers), no exceptions, if you wanted your car to last. But on modern vehicles, the interval between changes can be 10,000 miles (16,093 kilometers) or even longer. That represents big savings of time and money, not to mention giving a break to the environment by not having to produce and then dispose of those additional quarts of oil.

For more information about engine oil analysis, be sure to follow the links on the next page.

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Sources

  • Barnes, Mark. "Oil Analysis: Five Things You Didn't Know." MachineryLubrication.com. (June 4, 2011) http://www.machinerylubrication.com/Read/1704/oil-analysis-know
  • BobIsTheOilGuy.com. "Engine Oil Analysis." (June 5, 2011) http://www.bobistheoilguy.com/engine-oil-analysis/
  • BobIsTheOilGuy.com. "What Is Oil Analysis?" (June 2011) http://www.bobistheoilguy.com/what-is-oil-analysis/
  • Lubes-n-filters.com. "Oil Analysis." (June 2, 2011) http://www.lubes-n-filters.com/synthetics/oil-analysis.html#first
  • Reed, Philip. "What's Your Engine Oil Telling You?" Edmunds.com. Oct. 16, 2009. (June 1, 2011) http://www.edmunds.com/car-care/whats-your-engine-oil-telling-you.html