Emissions reductions. This has been the theme of original equipment manufacturers for nearly the last 50 years. We keep going back to this subject because everything that has happened since 1970 has been initially driven by the need to reduce the bad boys of exhaust. From then to now, emissions of carbon dioxide, nitrous oxide, unburned hydrocarbons and particulate matter have all been dramatically reduced from their early, unregulated days. Zero emissions is still the goal, and I have no doubt that one way or another it will be achieved.

For the most part, the reductions in emissions have been attained through advancements in hardware. Smaller displacement engines, better fuel management and improved transmissions, among others, have all made major improvements possible. The only place where engine oils have played a part is through reduced phosphorus formulations that have enabled catalytic converters to function.

Reductions in fuel and oil consumption. Not surprisingly, emissions reductions must include reductions in fuel consumption. That leads us to fuel economy. In the beginning, fuel economy was improved by reduction in viscosity. SAE 10W-40 oils gave way to SAE 10W-30 products. Were seeing the same scenario in the heavy-duty market today with the introduction of API CK-4 and FA-4. I think the heavy-duty market learned from the passenger car market about the perils of fuel economy testing.

The first shot at quantifying fuel economy was through fleet testing. Depending on the vehicle, the driving cycle and the driver, results could vary from net gains for the fuel economy oil to actual increases in fuel consumption. Besides, it was expensive to run fleet tests. A variety of vehicles had to be tested, and they needed to be driven many miles.

In an effort to eliminate as many variables as possible but still get some quantifiable measure of fuel economy, the five-car fuel economy test was developed. This test took five cars (hence the name) from various automakers and ran them on a chassis dynamometer through a specified driving cycle. A reference oil was run (SAE 20W-30 with no viscosity index improver), then a candidate oil was run, and the differences in fuel consumption were compared. The result was presented as a percentage reduction averaged over all five cars. The driving cycle chosen was the Federal Trade Commission emissions cycle, which seemed logical. The results were much more reliable and the cost to run was less than fleet testing.

The five-car test was replaced in 1986 by the Sequence VI-a single engine on a test stand-which is more reliable, less costly and able to present results more quickly. The procedure is the same: Compare reference SAE 20W-30 results to a candidate oil using a formula to correlate back to the five-car test. Since the introduction of the Sequence VI, there have been modifications in the test due to parts availability, new engines and so forth, but the results have been correlated back to the original test method.

Oil consumption has been effectively reduced by chemical changes to the oil formulations, as well as tightening the engine and improving seal materials. Its pretty tough to find any oil leaks with modern engines. Blow-by, which is as much oil as unburned fuel, is now recirculated through the intake system and burned as fuel.

Lower viscosity. As I mentioned above, lower viscosity has been a major route to improvements in fuel economy affected by engine oil. The progression of viscosity grades has been in fits and starts. Originally, SAE 10W-40 was the go-to oil for passenger cars. SAE 10W-30 replaced it in the mid-seventies, then it was replaced by SAE 5W-30. That stayed in place for about 20 years before SAE 5W-20 and SAE 0W-20 began to make their presence known.

In 2015, SAE added three new viscosity grades to the SAE J300 viscosity classification: SAE 16, SAE 12 and SAE 8. They were specifically requested by Japanese engine builders and oil marketers that were working on even lower viscosity products. We now have the first instances of SAE 0W-16 being specified by engine manufacturers. Meanwhile, Japanese OEMs are working on an oil category built around SAE 0W-8.

In order to create successful engine oils with these lower viscosities, base oils needed to be developed that offered higher viscosity index, more thermal and oxidative stability as well as lower volatility. These are the API Group III base oils now available in the marketplace. They typically have viscosity indices of 120 or higher and very stable molecular structures, and are able to provide the lower viscosities needed for SAE 8 oils while maintaining volatility levels consistent with older SAE 5W-30 engine oils. Of course, this comes at a price in refinery yields and available viscosities. Were really threading the needle here since viscosity and volatility are inversely related to each other.

Additive chemistry has also evolved. Where there used to be a dispersant, a detergent and an antiwear agent, there are now additional antioxidants and friction modifiers. A constant throughout oil formulations are pour point depressants (a.k.a. low temperature flow improvers), antifoam agents and viscosity modifiers.

As a result of the move to reduce phosphorus in the finished oil, supplemental antiwear agents may have been added, and-with the high-V.I. base oils-some seal conditioning agents may be added as well. Detergents have been revamped in some cases and more magnesium-containing materials are being used to reduce low-speed pre-ignition events.

Hybrid and electric vehicles. Unless youve been lost in the wilderness for some 10 to 20 years, you know by now that there has been a major push to bring electrically powered vehicles into the marketplace. Electric power is seen as the way to reduce vehicle emissions to zero. Theres a whole different story on why this is so important (Kyoto ring a bell?), and it has to do with worldwide agreements to lower greenhouse gases, mainly carbon dioxide, to save the planet. Im not going to wade into that swamp.

The first foray into electrification was production of hybrid vehicles. They are a combination approach that certainly reduces emissions to some degree, and improves fuel economy. The concept is simple: Use electric power for shorter trips and a gasoline (or diesel) engine for long hauls. The battery powering the electric motor would be recharged by the engine and by braking action.

The next step in the progression is to use the gasoline or diesel engine to continuously supply power to the electric motor and to not rely on the engine for any motive power. The end of this story is that the storage batteries on board would be recharged from the electric grid, and the gasoline or diesel engine would be removed completely.

Were part way on the road to this change, but there are still some huge stumbling blocks that have to be removed. There is no national distribution system for electric charging stations. Instead, there are some charging stations in select private and commercial parking lots, and many people who have committed to all-electric have installed charging stations at home.

Another issue is the fact that energy is energy, and whether the British thermal units come from burning hydrocarbon fuels or from power plants generating electricity, there will need to be enough energy to do it all. I wanted to see what this meant, so I dug into some statistics on fuel usage in the United States. The data, courtesy of the U.S. Energy Information Administration, are staggering in their sheer size! They found that 142.8 billion gallons of gasoline (not counting 14.4 billion gallons of ethanol) was consumed in 2017. Using my trusty calculator, I came up with the figure that replacing all of this gasoline/ethanol would require about 18 trillion additional BTU! That equates to about 61 billion kilowatt hours.

Pursuing this further, the U.S. produced 4 trillion kWh of electricity from all energy sources in 2017, according to EIA. This includes 30 percent coal, 32 percent natural gas, 20 percent nuclear power and 17 percent renewables, including hydroelectric as well as wind and solar. The additional electricity generation required to replace all of gasolines energy amounts to an additional 15 percent of electrical generation capacity that will have to be added.

As an old oil guy, Im not too thrilled to see the end of the internal combustion engine! The oil industry has been a rock in the world economy for nearly 200 years. It has provided the motive power for people and governments and has been a driving force in raising the economic wellbeing of many nations. So, given the rate of change and the average age of vehicles on the road, I suspect it will be a long time before the roar of an internal combustion engine will be lost.

Industry consultant Steve Swedberg has over 40 years experience in lubricants, most notably with Pennzoil and Chevron Oronite. He is a longtime member of the American Chemical Society, ASTM International and SAE International, where he was chairman of Technical Committee 1 on automotive engine oils. He can be reached at steveswedberg@cox.net.