What Is an Oil Analysis

August 25th, 2023 by

Person Checking Their Oil

If you ever had blood taken during a doctor’s visit and later been given the results, you have a personal analogy of a car’s oil analysis.  The concept is the same.  After flowing about the system for a while, oil, like blood, can give indications of what is going on inside that may not yet be big enough to be noticed externally. Lexus of Las Vegas is here to give you an overview of what oil analysis is all about. 

You won’t be able to analyze the oil yourself.  It takes a professional lab to do that. But there are organizations such as Blackstone Laboratories that will send you a free test kit that will take you through the process of extracting the oil. You send it back to them, and they send you a report of what they found. In the case of Blackstone, the cost of the analysis is $35.00. To get the best reading on your vehicle’s engine health, it is best to test oil toward the end of its time in your vehicle.

 

Oil Analysis Report Demonstration

What It Can Say About Your Engine Health

Key in the analysis is a breakdown of what kinds of metals have been found. The metric will be in parts per million. Excessively high amounts of metal could indicate undue wear occurring inside the engine, and the type of metal may point to its source.  Engines vary, but here is a general list of metals and what parts they may point to for excessive wear:

  • Aluminum: block, head, pistons
  • Chromium: Piston rings
  • Copper: Bearings
  • Iron: Crankshaft, cylinders, camshafts
  • Nickel: Steel parts (trace)
  • Lead: Bearings
  • Tin: Bearings, pistons
  • Titanium: Valves (rare)

Traces of some of these metals are to be expected through normal use, but the analysis should be able to flag excessive concentrations.

The analysis can also show non-metallic contaminants that may point to other problems. Potassium and sodium are byproducts of engine coolant, so seeing noticeable amounts of them in the oil could indicate that coolant is mixing with the oil, which could point to a head gasket failure. Silicon could indicate contamination from sand or dirt from a non- or poorly functioning air filter.

 

Get Your Oil Changed with Lexus of Las Vegas

Oil Health Is Also Indicated

Oil analysis can also indicate the health of the oil itself. Excessive fuel dilution from possible blow-by in the piston rings can make oil thinner and less effective.  The viscosity of the oil itself can also be determined to see how much it has changed from its original state.  A key figure is the Total Base Number (TBN), which is a metric of the level of additives that fight the buildup of contaminants.  If the figure is too low, the additives may have fought the fight and are now worn thin.  Soot in oil is generally a factor in vehicles with direct injection, like all diesel engines and several modern engines that feature direct-gas injection. You will also be informed of the levels of water contamination, and the level of both oxidation and nitration—two chemical reactions that degrade the oil over time. These results are unlikely to rise to a level of concern if you change your oil at factory-recommended intervals.

The bottom line is if you suspect an engine issue, or are activating an engine that has been idle for a while, this could be worth your time and money. It would be an ideal test when considering a specific used car, though having the ability to extract the oil and the time for the analysis results could be a challenge. If you have any additional questions about oil analysis, ask one of our Lexus of Las Vegas service professionals.