Truck Topics

Oil Analysis: A Worthwhile Investment

By Scott Loftis/Staff Writer
Posted Jun 15th 2011 1:07AM

Regular maintenance is a necessity for truck owners — whether it be a large fleet or an independent owner-operator. This maintenance can be expensive, but it certainly is preferable to a breakdown that leads to even more expensive repairs and downtime.
However, there is a process that can allow you to reduce maintenance costs without putting yourself in danger of a costly surprise. It’s called oil analysis.
Oil analysis means just what it sounds like — taking samples of engine oil for testing at regular intervals. By having the contents of the oil tested, drivers and fleet managers may be able to prolong the time between oil changes and save money.
Of course, the trend in the trucking industry for years has been to use long-drain interval oils in an attempt to extend oil life as far as possible. But oil analysis can help stretch the life of your oil even further, and it’s easy to do.
Fleet managers can work with their lubricant supplier to establish an oil analysis program, sending samples of used oil to the manufacturer. The manufacturer can then test the oil to check for issues such as contamination from other fluids or microscopic bits of metal.
A typical oil analysis consists of four tests:

Spectral exam
In this test, an oil sample is analyzed by a spectrometer to determine the level of metals and additives in the oil. This test will give analysts an idea of how quickly your engine is wearing.

Insolubles test:
The insolubles test measures abrasive solids tin the oil. Oil oxidation, which is caused by oxygen and accelerated by heat, forms the solids in the oil. This test will allow you to gauge the performance of your oil filter and how much the oil has broken down.

Viscosity test:
The viscosity measures the grade, or thickness, of the oil. Based on the original grade of the oil, analysts can determine whether the used-oil viscosity is in the proper range or if the oil may have been overheated or contaminated.

Flash Point test:
The Flash Point test measures the temperature at which vapors from the oil ignite. For any specific grade of oil, analysts know what temperature the oil should flash at. If it flashes at or above that level, the oil is not contaminated. If the oil flashes off lower than it should, then it probably has been contaminated, most commonly by fuel.

Although truck manufacturers and oil manufacturers typically recommend changing your engine oil at certain intervals, the truth is that every situation is different and many factors contribute to the proper interval. Among those is driving conditions. For instance, driving in stop-and-go city traffic can be much more stressful on your engine oil (and your entire truck) than driving on the open highway. Drivers who haul most of their loads in coastal areas where there is more salt in the air, or in desert conditions where sand particles are more common may need to change their oil more frequently.

Another reason oil analysis is becoming even more common and important for truckers is exhaust gas recirculation (EGR), which is designed to help today’s trucks meet stricter emissions standards. Put simply, EGR uses the truck’s cooling system to reduce exhaust-gas temperatures. This increases thereby the coolant temperature, in turn increasing the oil temperature. This can have a significant effect on oxidation and viscosity. All that can add up to increased engine wear, reduced power and poor fuel economy.

By having your oil analyzed on a regular schedule, you’ll be able to spot these trends and know exactly when the time is right to have your oil changed. Whether that’s more often or less frequently than your current schedule, you won’t be flying blind. Your truck will perform better, your engine will last longer, and you’ll have fewer maintenance headaches.