Engine Oil Tips for Fleets – Engine oils for heavy equipment have evolved over the years in keeping up with Tier 4 diesel engine technology. The best oil will help your fleet machinery and equipment work in tip-top condition. With winter coming, this is even more imperative. Demands on heavy-duty diesel engine oils have been changing with revolutions in engine technology and fuel formulations.

About 25 years ago, fuel sulfur levels were at 5,000 ppm, as this substance went through the piston rings and into the crankcase to form sulfuric acid. Additives in the oil were applied in an effort to neutralize that acid. However, with depletion of additives, oil changes had to be made.

On top of that, sulfur levels dropped and soot control issues cropped up, leading to a change in the way manufacturers set up and calibrated diesel engines. As a result, fuel soot formed in the crankcase, leading to the need for draining.

With the introduction of modern emissions equipment, the crankcase environment improved. But now oil oxidation is a concern.


Engine oil must form a protective film, which guards against metal-on-metal contact. There are many measures of viscosity, but the two most common are:

  • Kinematic
  • Absolute

An oil’s impact on fuel economy may range from 0.5 percent to four percent, depending upon viscosity. However, fuel economy gains from the right selection of oil could be lowered when the vehicle idles a lot or experiences changes in driving patterns, such as through heavy traffic congestion or frequent hard stops.

Measuring fuel efficiency gains when it comes to off-road fleets is even more difficult. However, the right oil can reduce warm-up times and result in less wear at startup due because of the better oil flow and pumpability in winter.

Shifting to a lower viscosity is often times a good idea for fleet machines. For off-road diesel equipment, 15W-40 is the go-to choice for many companies, particularly for older pieces of equipment with many hours on them.

Another factor that influences oil choice is work in cold weather climates, where 5W-40 (a fully synthetic product) may be a better choice if you’re not keen on changing oil when the temperatures warm up. You may pay a bit more for it, but you get peace of mind knowing your equipment will start up on the coldest of winter mornings.

The “W” signifies Winter in multi-grade oils such as 10W-30 or 15W-40. The letter to the left of the W shows how that oil performs at low temperature. Take 5W-40, for example, which flows more quickly through the engine in cold temperatures.

Conventional vs. Synthetic

Conventional engine oil uses only standard mineral-type base oils. Synthetic blend oil uses both synthetic and mineral oil. Full synthetic oils use all synthetic base oils. Synthetic oil is preferred by many for higher performance advantages, including resisting oil oxidation and improving oil flow in the cold.

That being said, there are multiple factors to be considered, mainly as they relate to the quality of the additive. Equipment owners would be wise to ask the engine oil provider for information on the performance claims of its engine oil options.

In general, synthetic blends or fully synthetic blends:

  • Have better cold weather performance and start-up
  • Are necessary in the formulation of lower viscosity heavy-duty engine oil grades
  • Have higher temperature performance

The higher performance of synthetic blends generally adds to the value to the end user. But its application is where things will differ.

Today’s engines run hotter, creating an oxidation concern. Synthetic oils have better oxidation resistance. They also offer improved cold temperature properties which is a must for the East Coast. Conventional oils are more affordable, yet they don’t work as well in cold weather applications.

The right answer when it comes to oil will depend on your specific needs and the goals you want to achieve when it comes to your maintenance program.

Contact Taylor Oil

Here at Taylor Oil, we only usethe best oils and lubricants for your equipment and engines. Contact us today to learn more.