From a lab:
Managers and analysts at Blackstone Laboratories often do presentations regarding the fascinating world of oil analysis. Regardless of the immediate topic, the most common question we hear is, "What type of oil should I use in my car?"
Because we're an independent laboratory, we don't recommend any specific oil brands. We always recommend using an oil grade recommended for your engine by the manufacturer and a brand that fits your budget.
You can go into any mass retailer (Wal-Mart, K-Mart, Meijer, etc. ) that sells engine oil and buy a 10W/30 (or any other preferred grade) that will perform well in your engine. One of the best-kept secrets of the oil industry is that these store brands are actually the same, quality oils that are produced by the major oil companies. The only difference between these products and the major company brands is the name on the container and about 50¢ a quart.
But wait! We do actually have a preference when it comes to buying oils for our personal use engines. That preference however, has little to do with brand names.
We analyze oils from our personal use engines (right down to our lawn mowers) religiously. We tend to choose oils that do not contain additives. Additives tend to get in the way of elements we want to see in the analysis data.
For instance, many light, multi-grade oils use compounds of copper and/or sodium as oil additives. The copper additive masks brass or bronze wear from the engine. Sodium additives can mask anti-freeze contamination.
There are many types of after-market additives you can buy. Some contain unusual compounds that can cause make it difficult for our analysts who are trying to determine if your engine has a mechanical problem. One additive we know of contains a lead compound. But lead is a metal common to bearing inserts. If you're using an additive with lead in it, it is difficult to tell whether the high lead is from your additive or a problem with the bearings.
Another type of additive we often run across contains silicone (which is read as silicon by our spectrometer). Silicon is often found in the oil when a fault exists at air filtration. If we do not know there is an additive in use, it can be difficult to diagnose true problems that may be producing high silicon.
If you are interested in having your engine oil analyzed by a quality lab, you will receive a better analysis if you avoid oils and after-market additives that use elements we need to see clearly to do a thorough analysis. If you feel you truly want to use an after-market additive, please let us know about it on the information slip provided with the sample.
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