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Why Choose Synthetic Motor Oil Over Conventional Oil?

Pennzoil Synthetic Motor Oils


The goal of stepping up to a full synthetic motor oil is to take better care of your car’s engine than conventional oils are capable of. A cleaner engine is better protected and more responsive.

All engines generate contaminants, such as soot, carbon, and sulfuric and nitric acid. These contaminants are inevitable byproducts of the combustion process. All contaminants end up in your motor oil to varying degrees. So the question isn’t whether you need an oil that cleans, but how well your oil cleans the dirt and deposits your engine generates. Synthetic oils perform better at both high and low temperatures.

Pennzoil Comparison: Synthetic vs Conventional Oil

Why Use Full Synthetic Oil?

Part of the job of an engine oil is to suspend the contaminants within the oil until your next oil change. It’s a fairly daunting task for engine oil to suspend all the contaminants thrown at it. Full synthetic motor oils like Pennzoil Ultra™ and Pennzoil Platinum® do a better job of preventing deposits on engine surfaces than conventional oils and synthetic blends can do. In fact, both motor oils exceed certain cleanliness standards that conventional oils and synthetic blends just can’t meet.*

*Based on GM4718M and Honda HTO-06 tests using SAE 5W-30.

Myths About Synthetic Oils

  1. Once you switch to synthetic oil you can never switch back. This is one of the most persistent myths about synthetic oil that is completely untrue. You can switch back and forth at any time. In fact, synthetic blends are simply a mixture of synthetic and conventional oils. It is advisable that you use the same oil for top-ups if needed, which will give you the best protection from the oil that you have chosen.
  2. You shouldn’t use synthetic oil in an older vehicle. This myth is rooted in the idea that synthetic oil is “slipperier,” lower in viscosity, or not as compatible with seals and will therefore leak or leak more in places conventional oil might not. Again, this is completely untrue. Synthetic oils will enhance the engine protection in older vehicles just as they do for new engines.
  3. You should break in your engine with conventional oil before you start using synthetic oil. Again, there’s no manufacturer we’re aware of that makes this recommendation. In fact, many cars are delivered from the manufacturers with synthetic oil, including Mercedes, Porsche, Corvette, some Cadillacs, Volkswagen, Hyundai and many others.
  4. Using a synthetic oil voids a car’s warranty. This myth is also not true. The only engines that specifically exclude the use of a synthetic motor oil are some Mazda rotary engines.
  5. Synthetics made from Group III base oils are not true synthetics and are not as good as PAO-based synthetics in Group IV. Again, this is not true. Synthetics made from Group III oil can, in some cases, outperform those made in Group IV oils in some areas of performance.

Change to synthetic motor oil at your next oil change at one of our Pennzoil 10 Minute Oil Change locations in Novato, San Francisco, San Rafael and Santa Rosa today!