The Busted Motor Oil Myths

Motor oil myths abound. Here are some facts

Customers who have “read something online” or heard something about motor oils call us to inform them that they don’t know the truth. Motor oils are often misunderstood by “armchair tribologists”, who, while genuinely interested in the subject, propagate myths. Below is a summary from a recent AMSOIL blog post about five myths.

Motor oil must be changed once it has turned black

Fact: Not necessarily. Many diesel applications can cause oil to turn black after being changed. The oil can become black if it is not removed from the engine. Blackened motor oil can indicate that additives have been working. Used oil analysis can tell you exactly when you need to change the oil. This is usually impossible to determine visually. This post explains why motor oils turn black and when it is time to change.

Oil must be changed every 3,000 miles (4,800 km).

Fact: quick-lube chains created this myth many years ago to keep customers returning. Initially, oils were low-quality. However, motor oil technology and motor oil are much more advanced today. Today, original equipment manufacturers (OEMs) recommend oil-change intervals that are longer than 10,000 miles (16,000 km) or longer. AMSOIL Signature Series can be used for up to 25,000 miles (40,000km) or one year. For more information about the 3,000-mile oil-change myth, click here.

Synthetic oil can’t be mixed with conventional oil

Fact: Synthetic and conventional motor oils share the same basic components, base oils and additives. Although synthetic oils have superior properties to their conventional counterparts, they can still be safely mixed. Some oil companies sold synthetic motor oils years ago that were not compatible with conventional oils. However, they were quickly taken off the market, and customers had to buy a quart of oil. Today, synthetic oils and conventional oils can be mixed. However, synthetic and conventional oils can be mixed. The lower quality oil will limit the performance of the synthetic oil compared to the conventional oil. Is it safe to mix synthetic oil and conventional oil?

 Synthetic oil is irreversible.

Fact: Since both oils are compatible, it is safe to switch back. We are asking why? Why would you change to synthetic motor oils with better performance and benefits?

 Synthetic oil causes engines to leak oil

Fact Bottom line: A synthetic oil may detect a leak but not cause it. If engines are not maintained correctly, they can develop cracks and wear seals. Sludge and deposits may cover the worn or damaged seals. These “false seals”, made up of dirt and sludge, can be removed by synthetic detergents that expose the worn seals. AMSOIL is a good synthetic oil that conditions seals to keep them flexible and prevents leaks. Use high-quality synthetic motor oil to ensure that seals are in this condition before they reach it.