The oil you put in your engine matters. After all, your engine contains many moving parts that must remain lubricated to work properly. Otherwise, your engine could develop some serious wear and tear. Even the most dependable car requires having the right motor oil.

All motor oils must follow certain guidelines. However, not all products on the market meet these guidelines. Luckily, the Petroleum Quality Institute of America independently tests motor oils, and we drew much of our information from them.

11. AB Lubes Supertech

AB Lubes Supertech does not meet any specifications set by any organization. Testing has also found that the viscosity is lower than it needs to be in warmer temperatures. Therefore, this oil may become less effective as your engine heats up.

This oil doesn’t claim to meet any specifications or guidelines. In fact, it says right on the container that you should use it with caution for this reason.

10. Cruz-In

Cruz-In doesn’t meet any standards and likely won’t properly lubricate your engine. The viscosity of the oil is much lower than the minimum recommended. Furthermore, it contains an abnormally high amount of silicon, which may indicate that it contains abrasives that would directly harm your car engine.

The PQIA has placed a consumer alert on practically all oils by this company, so we do not recommend them for any modern car on the road.

9. Lube 1 Oil

Lube 1 Oil isn’t recommended for use in any modern engines. It even states this on the package but does so in a roundabout way that may confuse consumers. It states that it’s comparable with SJ motor oils. However, these motor oils were designed for use in cars built before 2002 – to modern-day engines.

The viscosity of this oil isn’t the best and doesn’t meet any standards. It also contains high amounts of contaminants, which may indicate that it contains used oil.

8. Petrola Motor Oil

Petrola Motor Oil is one of the more interesting cases on this list. It’s marketed on the front label as “premium” and modern. However, it states on the back that it isn’t rated by the API and “is not suitable for use in most gasoline-powered automotive engines after 1930.” Obviously, we wouldn’t recommend using it in any situation.

This product doesn’t contain any additives that would protect your engine. It even states this directly on the back of the container. It also contains an unusual amount of iron in it, which may potentially be harmful to your engine.

7. Super Green Smokeless Motor Oil

This motor oil tries to slide under the radar by not including practically any information on the label. It doesn’t claim to meet any standards, and it certainly doesn’t meet those standards. It could easily harm any automotive engine you put it in.

For one, it doesn’t have the proper viscosity at a lower temperature. Therefore, it can cause issues if you run your car in colder weather. It also has an extremely high phosphorus content, which can harm your car’s catalytic converter and actually increase your cat’s tailpipe emissions.

There are also no meaningful additives that would protect your car’s engine.

6. Mileage 365 Lubricants

Mileage 365 Lubricants is another motor oil that just doesn’t meet the standards set. It lacks any potentially beneficial additives, leading to excessive wear and tear. It also has a poor viscosity when cold, preventing it from truly protecting your engine.

This motor oil also contains some worrisome additives, like silicon, copper, and aluminum. These hint that it may contain used oils and abrasive materials, making this protection unsuitable for car engines.

5. Sgt. P Motor Oil

Like many products on this list, Sgt. P Motor Oil does not meet the bare minimum to protect your engine. It did not meet the viscosity guidelines at several different temperatures, and it included far too many potentially harmful additives.

This motor oil also doesn’t contain good amounts of potentially beneficial additives like phosphorus. Therefore, it will harm practically any automotive engine that it’s used in.

4. Q10-40 Motor Oil

The PQIA has put a consumer alert on Q10-40 Motor Oil because it may harm engines. The label itself doesn’t claim to meet any standards. However, the motor oil does use leading terms, such as stating “10•40” in large print. It wouldn’t be hard to assume that this brand claims to meet the SAE 10W-40 viscosity grade.

After testing, the PQIA found that this brand doesn’t meet these viscosity guidelines. It isn’t suitable for practically any engine around today. It may also include harmful additives, which may lead to sludge formation.

3. Bullseye Motor Oil

Bullseye Motor Oil is another brand that has failed to meet very basic standards. The Petroleum Quality Institute of America found that this brand doesn’t meet API standards for viscosity, additives, and other necessary specifications. Therefore, it doesn’t protect your engine as well as other brands.

Specifically, this motor oil is well below the necessary viscosity to properly lubricate your engine. The lack of proper additives will likely cause excessive wear and sludge formation.

2. Questron Motor Oil

Questron Motor Oil is not a good option for any of the cars on the road today. The packaging continually uses phrasing that makes it appear to meet API SN/GF-5 guidelines. However, extensive testing has revealed that it does not. It should be labeled at a much lower grade.

It’s also high in unnecessary additives and unusually low in the needed ones. For instance, high levels of calcium and magnesium were found in the motor oil, which may cause excessive wear or build-up within the engine.

1. Xpress Lube Pro Motor Oil

Currently, Xpress Lube Pro Motor Oil isn’t recommended by professionals. It’s been criticized as being very low-quality and not meeting the standards set by the API. The Petroleum Quality Institute of America has tested Xpress Lub Motor Oil and found that they don’t meet key standards in several areas, including:

• Viscosity: Failed to meet basic SAE J300 guidelines
• Additives: Insufficient levels of required additives
• Contamination: Abrasive material present in samples

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