Owners of diesel trucks like ours who gather in boards like this typically are a "special breed".

Most of us are here because we recognize the superior characteristics of our trucks that deliver operating and lifespan characteristics far above typical gas powered vehicles. We're more than simply diesel truck owners, we're ENTHUSIASTS!

With that in mind, many of us look for ways to preserve the quality built into our trucks by various means - best possible lubricants - best filters, best waxes/polish, etc.

In the case of lubricants, especially engine oils, there are a wide variety of available brands and types - full synthetics, semi-synthetics, and a number of excellent conventional oils.

Then there are filters, varying brands and types, that cover fuel, air and oil filtration.

New diesel truck owners in groups like this soon wonder what oils and filters are best for their truck and their particular use - and what is the best change intervals for these items.

One long accepted "yardstick" for measuring the effectiveness of specific oils, filters and change intervals, is thru use of oil analysis. Lab testing of lube oils has been used by the commercial trucking industry for decades - and has become cost effective and more common down at our level in recent years.

Here's a photo of my last oil analysis, done at the conclusion of an extended drain test I did to see how long regular Dino based lubricant (Chevron Delo 400 15/40) would continue to meet physical lubrication requirements - the oil tested had been in my engine for 20,000 miles - mostly towing our 5th wheel RV.



The various line entries seen, display analysis results in Parts-Per-Million (PPM), of wear metals like Iron, Aluminum, copper, etc., various common oil additives like Boron, Zinc, and Molybdenum - as well as contaminents such as Soot, antifreeze and water.

In my case, my use of a Frantz oil bypass filter delivers extra filtration down into the sub-micron range (better filtering is a GOOD thing!), so my numbers at 20K miles are better than many un-bypassed samples at 5K miles - which was another point in my particular test.

So, what is the point or value in oil analysis? Well, it reveals the effectiveness of YOUR specific lube, filters and change interval in actual measured numbers - and gives comparison data vs common universal averages, and allows you to track the wear of your engine over time and make comparisons of various oil and filter brands, as well as comparing your analysis with that of others.

Oil analysis also gives you info on other engine operating parameters - high soot levels are an indication of improper fuel delivery - and resulting low fuel economy as well as lube contamination. Existence of antifreeze in the oil sample is indication of coolent leakage into the lubrication system - possibly a leaking headgasket. Excessive Silicon content may signal a poor or failing air filter, which in turn allows dirt ingestion into the engine - a BAD thing...

It is generally accepted that while there are a fair number of outfits doing analysis - Blackstone as I posted above, CAT, Oil Analyzers Inc., and a number of others - that a user is best off to start with one of their choice, then stick with them for subsequent tests.

This is because of common variations in company equipment, calibration, and types of test equipment - it has been clearly demonstrated that analysis of the same exact oil samples sent to several different companies CAN give significantly different results - not necessarily a bad thing, as long as you focus upon the TRENDS of the readings, rather than specific numbers.

That said, I personally, have had the best, most consistent and repeatable test results with Blackstone - they charge more than most others - about $20 per analysis - but their consistent results are worth the slightly higher cost to me.

So, there's a basic overview of oil analysis for new diesel truck owners - enjoy!