Your Car: Synthetic Oils versus Conventional Oils

Engine oil is the lifeblood of your vehicle. But many don’t know when it’s best to use a synthetic oil over a conventional one.

This Q&A provides answers to common questions about Petro-Canada synthetic oils, and why you might want to get a synthetic oil change the next time you top up.

1. When should I use synthetic engine oil?

Cold weather driving

Oil thickens significantly at low temperatures, slowing it from reaching critical engine components at start-up.

Compared to conventional oil, synthetic oil:

  • Provides improved protection at lower temperatures, which results in quicker, easier starts, minimizing wear on the engine. In fact, approximately 20% of engine wear occurs on start up.
  • Retains its superior low temperature properties, so you can expect this performance for the duration of the oil’s life.

Heavy loads

Your oil may be too thin to protect your engine. Maintaining film strength under high loads and temperatures is critical to preventing wear.

Synthetic oils:

  • Have superior film strength at high temperatures, protecting your engine against wear under heavy loads
  • Ensure you experience less engine wear and help you avoid costly maintenance

Stop-and-go traffic

Driving in stop-and-go traffic every day can really have an impact on the engine as it heats up beyond normal temperatures.

High temperatures cause thermal breakdown of the oil and deposit formation. Synthetics resist breakdown resulting in cleaner running engines with better performance and fuel economy.

Frequent short trips

Frequent, short trips cause sludge formation due to lack of warm-up. Low engine temperatures don’t drive off water from the combustion process and residual fuel, causing moisture.

Synthetics resist sludge formation and maintain oil flow for longer lasting engine protection.

2. How does Petro-Canada compare to other leading brands?

Petro-Canada meets or exceeds the latest industry specifications, just like the other major brands. In fact, numerous North American and Asian car makers have turned to us for their oil needs.

3. Are Petro-Canada’s products warranty approved?

Petro-Canada engine oils meet or exceed new car warranty requirements for North American and Asian vehicles where ILSAC GF-5 or API SN engine oils are recommended.

Always consult your owner’s manual to select the appropriate viscosity grade for your engine.

4. Can conventional oil and synthetic oil be used interchangeably?

Yes. Synthetic engine oils are fully compatible with conventional engine oils. You can switch to and from synthetic at any time and it can also be used for top-up. However, to achieve the full performance benefits of synthetic motor oil, we recommend you do a full oil change.

5. Can synthetic engine oils extend my drain interval?

Petro-Canada recommends that you follow your OEM's (original equipment manufacturer) oil drain interval recommendation.

However, synthetics maintain cleanliness and fresh oil properties longer and are more forgiving if you go past your recommended oil drain interval. Regular oil changes are low cost preventative maintenance measures that help keep your engine running in top condition.

SUPREME Synthetic

SUPREME™ Synthetic

Exceptional performance in severe weather conditions


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