Issue #2

If you ask this question of several “experts”, you will probably find a variety of opinions. Some experts will tout synthetics versus non-synthetics. Some will have a strong preference among brand names or refining techniques. Still others will promote various technical advantages such as extended drain capability, premium additive packages or a high viscosity index. (A “high viscosity index” indicates a lower rate of viscosity gain or loss as temperature changes.) All of these arguments may be valid, but for most people it is just too much information.

However, if you can stand one more opinion, I would like to offer a general recommendation for your gasoline engine (with only a short technical story). After 20+ years in the industry (and quite a few personal and work vehicles), I have developed a strong preference for semi-synthetic or synthetic blend engine oils.

With 2 adult children, our household is now running 4 gas vehicles. One is a newer pick-up and the other 3 cars are at least 5 years old. For each of our vehicles, the manufacturer's primary recommendation is a 5w30. The only provision is that the oil must meet the API specification that was current at the time of manufacture. (API SL is the code you should find on current packaging). In our case, we choose to use a premium semi-synthetic 0w30 year-round in all of these vehicles. Please note that this is not a warranty conflict with major manufacturers recommending 5w30. We have explored this for customers before and have always received acceptance from the manufacturer (although we sometimes had initial disagreement at the local level). In addition to the manufacturer's warranty, Petro-Canada offers a very strong warranty against any lubricant related failure.

My rationale for choosing a 0w30 is:

•  A 0w30 will provide superior cold-starting and wear protection in cold weather (versus 5w30 or 10w30). Even with modern engines that are designed to provide nearly instant oil pressure, it is still advantageous to have a lubricant that circulates readily at cold temperatures. Poor lubricant flow, even for a short time, will cause damage to metal components.

•  Surprisingly, at least to most people, you can also expect 0w30 to provide superior wear protection at high temperatures . The secret is that 0w30 has a lower rate of change with temperature. As temperatures within the engine exceed 100 degrees Celsius (the temperature at which engine oil viscosity is measured), the 0w30 is now at a higher viscosity than 5w30 or 10w30. There are hot spots in all engines, even under normal operating, and severe driving conditions (ie. Towing trailers in the mountains) can cause thermostats to struggle to keep temperatures within the acceptable range. Oils that maintain a higher viscosity at high temperatures will provide more film strength and better wear protection.

•  Most 0w30 engine oils are formulated as synthetic blends. The addition of some synthetic base stock provides many of the advantages of a full synthetic, but the costs are much lower for the blended base stocks. Semi-synthetics can provide excellent value in the engine oil category both through improved wear protection and longer drain capability, all at a modest price increase over conventional multi-grade oils.

I strongly believe that many of today's vehicles would benefit from a change to a semi-synthetic 0w30. However, please note that some new vehicles are now designed for 5w20 engine oil and you should be extremely cautious about selecting another viscosity oil for these new engine designs.

If you are interested in obtaining more information, we invite you to contact us directly or visit the Petro-Canada website http://www.petro-canada.ca/eng/prodserv/lubesgreases/6886.htm .