Will conventional oil whither?

As more and more cars come pre-filled with synthetic oil, and consumers are choosing to use synthetic oils in older vehicles, one can wonder what room is there for the conventional oils that have lubed engines for the last 100 years.
“You can still formulate a very strong mineral-based product that meets the requirements of the latest and greatest API standards,” said Anthony Stadelman, director of marketing for Wakefiled Canada, distributors of Castrol Lubrication Products. “Technology is constantly evolving, so basically what happens is that the industry collaborates on what are the requirements to meet the needs of newer engines.”
The reason we are seeing a gradual shift to synthetics oils is “Wear control is significantly better, deposit control is significantly better, cleanliness is better, it generally keeps everything cleaner, reduces sludge, oxidation and corrosion,” he said. “Across every metric synthetic will perform better in your engine.”
The march to higher quality oils is driven by the auto industry that needs better performing lubrication for newer engines. “Improvements in lubricant technology in the past decade have been mostly driven by fuel economy and emission system protection requirements,” said Jim Vitak, manager, public relations for Ashland Inc. distributor of Valvoline lubrication products. “Both synthetic and mineral motor oils have improved dramatically due to advances in additive, refining and processing technologies.”
The difference between mineral oils and synthetic oils is due to the base stock on which it is based. “Synthetic is (a) more refined base oil, a better base oil,” said Chris Hayek, global brand manager for Quaker State. “There are really two parts to motor oils. For simplicity, you have your base oil and you have your additive package. When you look at the difference between a conventional mineral oil and a synthetics, synthetic motor oil has a more refined base oil; it allows you to do more with your additive package.”
All oil used in vehicles is, roughly speaking, a blend of about 85 per cent base oil and 15 per cent of an additive package. “The term ‘synthetic’ is really focusing on the base oil part. API classifies the quality and performance of base oils by groups. Groups I and II are considered to be mineral oils, and Groups III and IV (and some in Group V) are considered synthetic,” added Vitak. “Synthetic base oils have better low-temperature properties, a high viscosity index, much fewer impurities such as sulfur, and better oxidative stability, among other aspects. Typically, synthetic motor oils are made from synthetic base oils (Group III and IV) and additives, while mineral motor oils are from mineral base oils and additives.”
The additives that are engineered into the base oil are, “What gives you wear protection and cleanliness and longevity,” said Jeff Hsu, Quaker State technology manager. “The base oil part keeps your engine well lubricated. Conventional oils are so well developed these days that some will rival some lower end synthetics. With high performance oils, synthetics are always superior.”
Another area where mineral oils lose out to synthetic oils is the weight category. Regular mineral oils cannot be engineered to the extent that synthetics one can and with more car manufacturers calling for thinner oils for their more efficient engines mineral oils will be less in demand. “The newer vehicles tend to be synthetic blend to meet their specifications,” said Hayek. “If you look at Toyota and Honda, as an example, they are going to zero-20. To get down to a zero weight, it has to be more of a synthetic oil.”
If a customer comes in and wants to upgrade to synthetic oil there should be no compatibility issues.
“It will work a whole lot better in low temperatures and that is very important,” said Hsu. “There are studies out there that show that during extreme cold starts that is where most of the wear happens. So a synthetic-based oil, with all the additives that are in it, will give the engine better protection during these cold starts. On the other end of the spectrum, cars are now designed with smaller and lower front ends this means that there’s less forced air going through the engine. A synthetic’s ability to remove heat is also very important. If a customer comes in and wants to move to a synthetic there is an advantage to this.”
He said the only car that he would not recommend synthetic oil in is older Mazda RX7s. “The Mazda RX7, older rotary engine burns a lot of synthetic oil. That is the only car that comes to mind that I would not recommend synthetic oils. The newer rotary engines on the RX8s are fine and are even factory filled with synthetic oils.”
Stadelman said there are performance benefits for changing to synthetics oils in older cars he said in some cases the switch will not bring about any benefit, “In some older vehicle applications where there is already damage to the engine. Because synthetics are generally thinner and more slippery you will tend to loose more oil in those cases. And because of the new additive, this isn’t really the best for some older engines. For any modern engine there is no problem.”
If a customer, for some reason switched to synthetic oil and wants to switch back to mineral oils because of cost, this is also not a problem any more. “The design of the formulation these days has included considerations of compatibility and performances,” said Vitak. “One of the early concerns was the seal compatibility of the synthetic base oils. The development of novel and advanced seal conditioning chemistries solved that problem completely.” He cautions that switching back, although it won’t damage the engine or the seals, “Synthetic motor oils do provide better performance – so switching back may result in some loss of performance.”
Mineral oils will still be on the shelf for a long time as there are lots of cars out there that will work fine with them and the additive packages engineered for them will rival some of the lower-end synthetics. However, the inherit benefits of a proper synthetic oil will always be better for an engine. “We did a simple test where we would start an engine that has been sitting in minus 50 degrees to measure the difference between synthetic and conventional oils,” said Hsu. “It takes about two-and-a-half to three seconds for the oil to start flowing properly. If you are looking at 7,500 kilometers between changes and you add up all those seconds you are talking about ten to 15 minutes of oil starvation.”