Engine Oil Change Myths, Part 2

In our last post, we explored the first two oil change myths that you may have heard: that dark engine oil is dirty and requires immediate changing, and that the W in 10W-30 engine oil stands for weight. Now for the final three misconceptions about engine oil!

Engine Oil Change Myths, Part 2

You Need to Change Your Oil Every 3,000 Miles

Somehow, the 3,000 mile myth got started, and it’s still circulating today. According to this oil change myth, after 3,000 miles your St. Louis| Engine Oil Change Myths, Part 2engine would start filling with sludge, decreasing your vehicle’s performance and leaving the engine’s moving parts at a higher risk for damage.

Engine Oil Change Myths, Part 2

Despite the rumor’s persistence, it simply isn’t true any longer. Perhaps this was once the case, but the invention of modern engine oil has rendered the 3,000 rule irrelevant. Engine oil now has better viscosity — this coupled with improvements to automobile engineering overall ensures that most modern cars can run 7,500 miles without an oil change. Be sure to check your manufacturer’s specifications to see when an oil change is needed for your specific vehicle.

You Should Use Engine Oil Additives

While engine oil additives do help your engine perform better, the truth is that many of these additives are already in the regular oil. Most good brands of motor oil contain additives to improve their viscosity under various temperatures. Plus, they have the additives that prevent sludge from forming and building up in your engine, along with rust retardants that stop corrosion.

What’s the harm in adding more? When the good stuff is already in your motor oil, putting in extra can dilute what’s there and make your oil less effective. You can always consult your manual to see any specific needs for additives — but chances are your run-of-the-mill vehicles don’t require anything extra. So on your next oil change, avoid those additives!

Synthetic Oils Cause Engine Leaks

Synthetic engine oils became popular in the 1970s. In their early days, they didn’t do so well with an engine’s seals or gaskets. Sometimes, they’d make engine seals shrink, causing oil leaks. As a result, there’s a lingering oil change myth that says you should avoid synthetic oils lest you want a leaky engine.

As with our other oil change myths, this is outdated information, as developments in engine oil and the automotive industry have fixed the issues leading to synthetic oil leaks. Synthetic engine oil no longer causes seal shrinkage, so don’t worry about oil leaks caused by that. However, you should exercise caution when using synthetic engine oil in an older car that has used petroleum-based oil for some time. This is because synthetic engine oil can clean sludge off the seals, and the sludge may have been blocking minuscule cracks in your engine seals. When these existing cracks are uncovered, leaks may occur. If your car is over 15 years old and has been running on non-synthetic engine oil for years, avoid switching to synthetic at your next oil change.

Reliable Auto Service in St. Louis

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