Fluid Factoids Part I: The Mystery of Motor Oil – Synthetic vs Conventional
Question: How do I know what type of engine oil is right for my car?
If you Google this topic you’ll get thousands of different answers from thousands of different sources. The debate over engine oil has been raging for decades and spans far beyond the age-old “synthetic vs. conventional” dispute. Oil is the lifeblood of your engine and without it–well… you know what can happen. So if you’ve ever found yourself standing in front of the “wall ’o’ oil” at the local parts place with a blank stare and a puddle of drool slowly accumulating under you, then hopefully this article will help make your next oil purchase a little less er… drooly.
Oil “Au Natural”
Old-head racers have preached the gospel of conventional oil since synthetic stumbled onto the scene back in the 70’s, but technological advances have left conventional oil in the dust. The term “synthetic” is really a misnomer – synthetic oils are made from the same base ingredients as conventional oils. Chemical reactions are then used to re-form the molecules to obtain desired characteristics. In a sense, synthetics are really just genetically modified conventional oils. Synthetic oils (such as Royal Purple) can withstand extreme engine temperatures and have a much wider range of viscosities (down to 0W-30!) making them a no-brainer when compared to conventional oils. All that comes at a price, however – $4 – $5 more per quart – so to get the benefits of synthetic at a price that’s easier on the pocket, a synthetic blend would be ideal.
Variations on Viscosity
The Golden Rule of oil viscosity set down by the automotive gods is this: ‘Though shalt use whatever thine manufacturer specifies.’ This holds true for most applications – check your owner’s manual for the proper weight for your vehicle. Viscosity is the measure of a liquid’s resistance to movement – the lower the number, the less viscous (or thinner) the oil. Dual-weight oils have become the norm for modern cars (ex. 5W-30) – the first number being the viscosity at 0˚F (aka “winter weight”), the second is the viscosity at 212˚F. Oil is engineered to be thinner at colder temperatures to provide the least resistance at startup, since that is when most engine wear occurs.
The 3,000 Mile, $64,000 Question
Mustang oil filter and oil change intervals can vary from one car to the next. 2010 Mustangs set the oil change interval at 7,500 miles/6 months (under normal operating conditions); this is another case where your owner’s manual comes in handy. Your Scheduled Maintenance Guide will tell you whether you should follow the normal maintenance schedule or the special operating conditions schedule. It’s better to err on the side of caution – you won’t hurt anything by changing your oil every 3 months/3,000 miles so if you’re not sure which schedule to follow you can always default to the tried-and-true.
In the world of aftermarket modification it’s easy to stray from the manufacturer’s recommendations, but this is one area where you want to rely on your owner’s manual for support. Replacing your oil with the proper weight at the specified intervals is one of the easiest ways to make sure your Pony keeps kickin’ for years to come.