13 Engine Oils That Are Almost Car Poison

While topping our cars’ engines with oil might seem mundane and dull, selecting the correct oil is essential. A higher-quality oil brand will be kinder to your engine and prevent further problems.

You might not think it matters, but it does. Some oil is too thin for some engines, while others might lack all-important additives that ensure they look after your engine.

Based on those factors and others, we have produced this list of the 13 absolute engine oils that are poisonous to your car. Other factors that come into play include whether the oil contains abrasive materials and how it performs in cold temperatures.

AmazonBasics

It seems like there is nothing that Amazon doesn’t do, and their AmazonBasics range also does some synthetic oils for your car engines. As you would imagine, the Amazon oil is priced as cheaply as possible compared to a more prominent brand, costing under $25 for a five-quart bottle.

Naturally, the cheap price reflects in the quality. It lacks some of those all-important additives, and it’s certainly not at the top of the list of options for buyers. Yet reviews suggest it does an optimal job, so of all the oils on this list, Amazon’s is one of the kinder for your engine.

Mileage 365 Lubricants

Mileage 365 Lubricants are some of the worst on the market and regularly fail to uphold the industry standard. According to 24/7 Wall St, Mileage 365 oils lack many beneficial additives important to engines, including those that prevent excessive wear and tear.

One of the other issues with the oil is its poor viscosity, mainly when it is cold. This prevents the oil from adequately protecting your engine, and while there are some additives, they are not good. Silicon, copper, and aluminum could all damage your car’s powertrain in the long term, so it is best to be wary of Mileage 365.

Sgt. P Motor Oil

A quick online look will reveal some pretty negative things regarding Sgt. P Motor Oils. One forum thread calls it “The Engine Destroyer.” Those forum posts suggest that the oil lacks many of those all-important additives, with 24/7 Wall St backing up those claims while pointing out the issues with the oil’s viscosity.

The viscosity is just as bad as on Mileage 365 Lubricants, which causes poor performance in colder temperatures, made worse by the apparent lack of those additives. Some buyers were put off the product by misspelling specific words on the website for Sgt. P’s oil and oil is “certified” by the API when they issue licenses, but they do not certify oil.

Super Green Smokeless Motor Oil

One thing that customers like about any product they are buying is the transparency of the labeling. Regarding motor oil, the labels can mean transparency about what is in it, its various viscosities, and how it complies with industry standards. Sadly, Super Green Smokeless Motor Oil lacks all that transparency for some consumers.

However, that isn’t the end of the problems associated with Super Green oil. In 2019, the Petroleum Quality Institute of America issued a consumer alert, stating that they had done so “due to its high viscosity, absence of additives vital to protecting an engine from deposits and wear, high phosphorus content, and labeling violations.” The alert also stated, “Use of this product in virtually all automobile engines will likely cause harm to the engine.”

Bullseye Motor Oil

Another famous oil brand is Bullseye Motor Oil, which fell following a quality alert from the Petroleum Quality Institute of America. This time, a warning was issued in 2012 that simply said, “Don’t Buy” Bullseye Motor Oil due to the significant damage it could do to some people’s engines.

This followed from issues reported in 2011 with Bullseye oil in Michigan, and the test concluded that the oil was far off the specification listed and potentially damaging to various car engines. The PQIA website states that “test data on this sample indicate it may contain used oil and has high levels of aluminum, iron, and silicon. In addition, the product has virtually no zinc, which is a vital antiwear additive in motor oil.”

Petrola Motor Oil

Petrola claims that its motor oil is premium and proudly proclaims this on its products’ labels. Yet, for all of its claims, Petrola oil is yet another for which the PQIA has had to issue a consumer alert, and it did so most recently in December 2017.

After visiting a convenience store in Ohio, the PQIA found Petrola on the shelves, a brand of oil that consumers are advised not to purchase. The labeling came back to bite Petrola, as the PQIA claimed that “the labels on the products do not comply with the Fair Packaging and Labeling Act (FPLA), or the Uniform Packaging and Labeling Regulations, each of which requires the product labels include a declaration of responsibility (name and address of manufacturer, packer, or distributor) of the product.”

Quaker State Oils

According to Get Jerry, Quaker State Q Motor Oil is another option consumers should avoid. They claim that while it is more expensive than a higher-performance oil, it also has a high volatility rate due to a lack of essential additives that ensure an engine runs smoothly.

Users on various forums back up this claim. Car Talk Community is one outlet that discusses this, saying that the brand’s reputation went downhill partially because of what its rivals were doing. Some users also reported that it caused their oil pressure to drop. Consistency with the quality of Quaker State oils appears to be a big problem.

Liberty Gold Plus SMO 5W-30 Motor Oil

According to the PQIA, two of the absolute worst motor oils for any car are Liberty Gold Plus SMO 5W-30 Motor Oil and Bullseye Automotive Products High Mileage 10W-30 Motor Oil. We will focus on Liberty in this entry. The PQIA says, “The viscosity for the 5W-30 tested is nearly 70% below where it should be,” while additives are less than a quarter of what OEMs recommend.

Liberty Gold’s oil also falls foul of mislabelling. Liberty claims that it protects against wear, sludge build-up, and rust. Worryingly, the PQIA found this was not the case, saying, “This product clearly is not a 5W-30 and does not meet any recognized specifications for a motor oil.”

Cruz-In

Cruz-In’s oil products are yet another brand for which the PQIA has had to issue a consumer alert. Worryingly, the warning was issued in the fall of 2017 for virtually every oil the brand has on sale. The website shows the alert was for poor physical properties, elemental analysis, and poor labeling.

The PQIA has a viscosity slider measuring it per cSt, and Cruz-In’s oil scores poorly at just 4.6 cSt, which is well below the standard. While its cold-cranking score of 2.193 is within the standard range, it is still on the lower end of the spectrum.

Mileage 365 Lubricants

The biggest issue facing Mileage 365 Lubricants is that any potential additives within the oil are simply non-existent. The oil fell foul of yet another PQIA consumer alert in 2017, and one of the other issues facing the brand’s 5-30 oil was its poor labeling.

The PQIA slams this inadequate labeling and says that “although the back label of the product states “5-30 means a motor oil with a viscosity ranging from 4 cSt to 12 cSt @ 100° Celsius,” this viscosity range is not consistent with any multi-viscosity motor oil as defined by SAE J300.” Equally disturbing is that the label fails to display the manufacturer’s name and contact information.

Q10-40 Motor Oil

A quick look at the PQIA website reveals that Q10-40 Motor Oil was the subject of a consumer alert in 2017. If the strange labeling styling wasn’t troubling enough, the revelation that it can lead to a build-up of sludge and corrosion within an engine is even worse.

The most damning reference to the oil is where the PQIA says that “se of this product in virtually all automobile engines will likely cause harm to the engine. Similarly, although the back label on the product states “Suitable for Moderate Diesel Engines,” use of this product in virtually all diesel engines currently on the road will likely cause harm to the engine.” All of this suggests that Q Motor is lying to the consumer.

Questron Motor Oil

Subject to yet another PQIA alert is Questron Motor Oil, although this one is more recent, taking place in January 2020. An alarming warning on the webpage says that “use of this product in virtually all automobile engines will likely cause harm to the engine.” Once again, many problems stem from a company openly lying about its product.

The PQIA says that “the labels on this product are false, misleading, and deceptive by prominently displaying “SAE 10W-30 PREMIUM SN-GF5 MOTOR OIL” and stating that the product “meets the latest in automotive manufacturer’s requirements.”

Xpress Lube Pro Motor Oil

The PQIA issued a consumer alert for Xpress Lube’s 5W-30 motor oil in July 2017, and it’s by far one of the worst oil products on this list. The PQIA gives a damning verdict on it, saying that “the organometallic additive levels in this sample indicate the product is NOT suitable for use in the majority of automobile engines currently on the road.”

The PQIA also condemns the oil’s label, saying it does not meet the specifications for the SAE Viscosity Grade on the label while adding that the oil contains many abrasive materials. If you see any for sale or lying around, avoid Xpress’s oil like the plague.