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Worst Oil To Put in Your Engine

The Petroleum Quality Institute of America is out with advice on what is the worst oil to put in your engine and it might surprise you where you can buy it.

The Petroleum Quality Institute of America says Liberty Gold Plus SMO 5W-30 Motor Oil and Bullseye Automotive Products High Mileage 10W-30 Motor Oil (SC/CC) are the worst oils to put in your engine because instead of making things run more smoothly they can stop your car dead eventually.

PQIA, which is based in Methuen, N.J., bills itself as "The independent resource for information and insights on the quality and performance of lubricants in the marketplace." It bought the two oils in question this month and last in Ohio and Michigan at different times so not just one batch of oil was tested. Their sample test results showed what was inside the bottles didn't match the labeled viscosity or its resistance to flow. The lower a fluid's viscosity the more easily it flows. Think water vs. molasses. Water has low viscosity. Molasses doesn't.

You don't want molasses pouring through your engine, nor do you want water pumping through your pistons. Extremely low viscosity oil would have the effect of water going through your engine.

According to Thomas F. Glenn, President of PQIA, "The test results for these products are the most concerning we have seen to date." To express these concerns Glenn says, "The viscosity for the 5W-30 tested is nearly 70% below where it should be, and the level of additives is less than a quarter of that required by original equipment manufacturers (OEMs) to protect automobiles currently on the road." Similarly, the 10W-30 PQIA tested has a very low viscosity and lacks the additives required to protect an engine from wear and corrosion.

The PQIA summary of the two motor oils is disturbing to read. Liberty Gold Plus SMO 5W-30 Motor Oil provides protection against wear, sludge build-up, and rust. It also claims to help your engine start better in cold weather (because of its low viscosity). Yet, PQIA found " this product clearly is not a 5W-30, and does not meet any recognized specifications for a motor oil."

The news gets even more distressing the further you read on when you discover that this oil, instead of helping your engine, actually includes high levels of silicon, an abrasive material that can wreak havoc on an engine. In other words, this oil does the exact opposite of what it claims to do and enhances wear on your engine.

The Bullseye Automotive Products High Mileage 10W-30 Motor Oil doesn't fare any better. Its label claims it is an SAE 10W-30 "high mileage" motor that "helps keep the engine clean, provides wear protection, helps prevent engine leaks, and fights rust and corrosion"

Well, as you may have guessed by now, it's not an SAE 10W-30 oil. But here's the real kicker. Just like the Liberty Gold Plus,does not meet any recognized specifications for a motor oil it. The viscosity for this oil is more than 75 percent below where it should be for a 10W-30 and lacks critical additives required by original equipment manufacturers to protect automobiles currently on the road.

PQIA, which likes to announce that it names the names of products and where they were bought, points out that consumers might have a false sense of confidence when buying these products because they were for sale at a Shell station. After all, Shell is a major oil corporation, the thinking goes, so the oil products sold at its stores must be good to purchase.

Well, that's not entirely true. PQIA reached out to Lisa Davis, President for Shell Lubricants, Americas, to address the issue. She told the trade group “Like many other major gasoline brands in the U.S., the name on the station sign reflects the brand of the motor fuel being sold at the station, while the convenience store and day-to-day site operations are the responsibility of the site owner and/or operator. While Shell doesn’t dictate the brand or quality of non-fuel products carried by the independent operators of these stations, we do expect items sold at Shell-branded retail stations to be quality, on-spec products."

Davis, according to her statement to PQIA, has made a commitment to cleaning up the non-petroleum products sold at Shell stations (but isn't oil a petroleum product?) She said, "In reflecting on this situation, I believe the independent owners and operators of Shell-branded retail stations could benefit from education on the importance of offering consumers quality motor oils, such as the API- or OEM-certified oils described in vehicles’ owner’s manuals."

Want to know the best way to avoid putting the worst oils in your engine? Don't skimp on the purchase price and go with synthetic oils from major brands like Mobil1. Purchase oil from auto parts stores and not convenience stores. Oil is the lifeblood of your engine. Don't save a buck and risk hundreds of dollars in repair work for your engine.

Keith Griffin has been writing continuously about new cars since 2002. He used to be the guide to used cars at former as well as a contributor to The Boston Globe and Automotive Traveler. He is the founder and president of The Internet Car and Truck of the Year, where "Internet Pros and Average Joes" pick the car and truck of the year. Currently, Keith is the managing editor for American Business Media. Follow Keith at @indepthauto on Twitter.


Albert (not verified)    January 27, 2013 - 9:07PM

Yeah I never heard of the bullseye oil until I had to skimp because my local store was out of my20w-50 I usually buy. So I proceed to poor this new black oil and I was like hollllly sh*+! Then I smelled it and knew right away it was used. I have a hi-po 5.0 engine with expensive internals and i know a motor, I'm not stupid, but This sure did make me wonder. Good thing I changed my Oil the next day and ran royal purple to sooth my baby! I am going back to store and taking bullseye off the shelf for them! And as for the owner operator of this company, I urge him to come here so i can give him a Georgia asswhoopin for selling bs

Yoleberry (not verified)    May 9, 2017 - 6:17PM

I was given five quarts of bullseye motor oil. I was goin to put it in my lawnmower. I opened a bottle and it smelled like the old reconditioned oil from the 1960,s that people used on cars that burned a lot of oil. The look and feel was not like any oil I had ever seen. I decided that it would not even be safe for my lawnmower.

Yoleberry (not verified)    October 22, 2018 - 9:26AM

I was given ten quarts of bullseye motor oil a few years ago. I use it. For one works as a lube on my chainsaw. I wouldn’t put this stuff in anything else. I wouldn’t even put in an old lawnmower.