ABC's of Oil Analysis

Kevin Dinwiddie

dinwiddieK@earthlink.net

Most everyone has a favorite brand of oil that they use in their car or truck. The question we must ask ourselves is whether our favorite oil is protecting as well as we think? Oil analysis can answer that question as well as some others that concern what may be going on in our engines. Oil analysis allows us to receive comprehensive data in specific categories that are relative to engine wear. Those categories are: wear metals, contaminant metals, additive metals, non-metallic contaminants, and the lube fluid data. Each individual oil analysis will give you numeric values that you can compare against unit averages that have been compiled. Furthermore, each additional sample you have analyzed will tell you more than the previous one because of the trend that you will establish.

Taking the oil sample is easy. First, contact a laboratory close to you (I use CTC at 1-800-524-7848). Ask the laboratory to send you a sample bottle and information form to provide information on your truck or car. Depending on the laboratory, the sample analysis will cost between $7.50 and $20.00 for each one. The best way to retrieve a sample is to suck the oil out from the dipstick hole into the bottle with a suction gun. I purchased my vampire suction gun from EZ VAC Inc. at 1-423-691-7510 for about $20.00. Another way to get a sample is from the drain plug. If you decide to take the sample from the drain plug: First, clean off the pan and plug to keep any contaminants out of the sample. Then, allow some oil to drain out before filling the bottle. If you take the sample from the oil drain plug, make sure that you indicate where the sample was taken from in the comment box on the sample information form. Always make sure that you bring the engine up to operating temperature before you take any sample. Finally, your last step is to seal up the sample bottle and fill out the information form. Pack it away in the shipping container and send to the lab for analysis.

After your sample has been analyzed you will receive a comprehensive analysis form: The first category you will look at will be the wear metals category. The wear metals category has 11 elements that are evaluated. Values for each element are given in parts per million or (ppm). For example a value of 40 for iron would tell you that you have 40 parts of iron per million parts of oil sample. The 11 wear metals are described below:

1. Iron: comes from Cylinders, Gears, Rings, Crankshafts, Liners, Bearings, Housings, and Rust.
2. Chromium: comes from Rings, Roller/Taper Bearing, Rods, and Platings.
3. Lead: comes from Bearing Overlays, Additive in gear oil and gasoline.
4. Copper: comes from Bushings, Bearings, Thrust-Washers, Friction Plates, Oil Cooler, and Additives in oil.
5. Tin: comes from Bearings, Bushings, Pistons, and Platings.
6. Aluminum: comes from Pistons, Bearings, Pumps, Blowers, Rotors, and Thrust-Washers.
7. Nickel: comes from Valves.
8. Silver: comes from Bearings, Bushings, and Platings.
9. Manganese: comes from Trace elements in liners and rings, or is an Additive in gasoline.
10. Titanium: is a trace element.
11. Vanadium: is also a trace element
    

There are only 4 contaminant sources listed on the oil analysis: (also displayed in ppm)

1. Silicon: is sometimes used as an anti-foam agent, but is most likely airborne dirt and abrasives in the oil. Silicon can also be from gasket sealer if work has been done recently.
2. Boron: is in most anti-freeze systems and cooking system inhibitors, but is sometimes used in oil as an additive.
3. Sodium: is also in most anti-freeze systems but is also used in some oils to fight off acids.
4. Potassium: is also in anti-freeze systems but is also used as an additive in gear oil. If your oil analysis shows the combination of Boron, Sodium and Potassium then you should have your engine looked at for a coolant leak into your oil.
   

Additive metals are also reported. These are the "good" metals. They are part of the formula that the oil companies use to enhance the oil's ability to perform. These values are also going to be given in parts per million (ppm)
Magnesium, Calcium and Barium: are all dispersant/detergent additives. These additives keep the foreign particles from sticking together and keep them in suspension for the filter to take them out of the oil.
Zinc, Phosphorus, and Molybdenum: are anti-wear additives and will enhance the oils ability to reduce wear. When looking for an oil that you want to for extended drains you should look for an oil that uses a lot of magnesium as well as having a robust zinc phosphorus additive package.

The non-metallic contaminants consist of Fuel, Antifreeze and Water. These values are shown in percentages (%). For example, a high fuel percentage indicates there is unburned fuel in the oil and may signal an incomplete combustion problem. Fuel soot may result from incomplete combustion or overextended oil drain intervals. Water and antifreeze are also non-metallic contaminants and any percentage is not good and should be investigated.

The lube fluid data is the next category you will find on a good oil analysis. Not all oil analysis companies do complete lube fluid data. The lube fluid data will consist of a Viscosity value and the TBN or Total Base Number.

Viscosity is usually measured at 100 degrees Celsius denoted in cSt. The values of cSt for a Specific SAE range are as follows:

• SAE 20 has a cSt range of 5.60 to 9.29.
• SAE 30 has a cSt range of 9.30 to 12.49.
• SAE 40 has a cSt range of 12.50 to 16.29
• SAE 50 has a cSt range of 16.30 to 21.89.

The Total Base number is a value that shows the oil’s ability to fight off acids. TBN is measured as the quantity of acid fighting additives that a given sample contains. The TBN of new oil should typically range from about 6 to 10 (10 being better) and should not deplete to 50% of the original amount. Hence a 10 should not deplete to below a 5. I recommend that in diesel applications that the TBN start at 8-10 and not go below a 5. In gasoline engines I recommend starting with an 8-10 and not going below a 3. In today’s diesel engines, using the lower sulfur diesel fuel that is available for on-road applications, a TBN value over 10 is not necessary even in extended oil drain situations. Off-Road and high sulfur diesel fuel usage requires oil with higher TBN numbers to combat the acid produced by the increased sulfur in these fuels. Gasoline engines also need not use oils exceeding a TBN of 10.

If you are going to start oil analysis, you should send a sample of new (unused) oil in for an analysis along with the used oil. This will give the laboratory a base line to compare the new oil with any other samples of the used oil you will provide in the future. Many Laboratories already have baseline information on some of the more common oils on the market. It is a good idea to call the lab first to see if they require the baseline information on your oil.

Let's talk about some of the things that can confuse us about oil analysis. Let's say that you just worked on your engine or had someone work on it. If you/they used silicon sealer to seal gaskets or engine components, when you do an oil analysis high silicon readings may show up. This may send you into a panic for nothing, as it might not be the dirt that you think it is. On the Analysis form that you submit with your sample there is a comments section. The comments section is for you to indicate any areas of concern you may have with your sample. You may want to include in this comments area that the engine has just been worked on. For example, making the indication “Rear main seal replaced”. A good analyst should pick up that the silicon level is elevated due to sealant use.

Another cause of confusion from some trucks is the copper level. Copper is an additive in some oils but you would not know this unless you asked the manufacturer of the oil or sent a new sample of oil in for analysis. Occasionally copper will show up and it can give you the false impression that you have a bearing problem. A true bearing problem would show more than an isolated high copper reading. It would more commonly be found in the company of high Tin and Lead readings. If you only have Copper showing up on your analysis, then you most likely are seeing copper oxides from an oil cooler or the oil manufacturer uses copper in its additive package. Some oil companies employ significant amounts of copper in their additive package. Copper from an oil cooler is not a problem at all. It is most likely an indication of a robust detergent/dispersant package doing its job. So when you see copper don’t panic, you need only be alarmed if you have all three (Copper, Tin and Lead).

Oil Analysis And Using a By-Pass Filter In Addition To Your Regular Spin-On Filter:

I recommend using a good bypass filter. However, by using a bypass filter you can be fooled into thinking that your engine is being subjected to less wear. Every oil has a specific wear rate built into it some are lower than others. You will not get any lower wear rate than when the oil is first out of the bottle. You will however get a lower wear rate than the average oil if you use a superior oil like Lubrication Engineers Monolec Ultra 8800 15w-40. Here is why…

Let's say you use an average oil and don't use a bypass filter. When you do an oil analysis you might see something like 40ppm of iron in 4,000 miles. Then you install a bypass filter and send an oil analysis in with 4,000 miles on it. You then see a reduction of wear metals that is now giving you a 25ppm of iron reading. You would think that engine wear has been reduced due to your installing the bypass filter. This might not be true. You may have the same wear rate, but now the 15 ppm of iron is being collected by the bypass filter instead of being dropped into the oil. Thus the bypass filter is masking the real wear that is still happening. Fortunately there is an answer. That is to find an oil with a robust anti friction, anti wear package like the Lubrication Engineers Monolec Ultra 8800. Lubrication Engineers uses a robust additive package that is made to reduce wear and friction thus not allowing the particles to get into the oil in the first place. The bypass filter will keep the oil in better shape longer so you can extend oil drains out farther. The Oil is the key to reducing engine wear.

If you are interested in purchasing Lubrication Engineers Monolec Ultra 8800 Oil, it can also be purchased at Mag-Hytec at 1-818-786-8325.

I hope that this information helps you understand oil analysis and take better care of your investment.