‘You save money. That’s it’: Expert shows what really happens when you put regular gasoline in a luxury car that lists premium

Imagine this: You recently bought a luxury vehicle. After the purchase, however, you discover a recommendation to use premium gasoline with your particular make and model. 

But do you really need to fork over extra cash every time you fill your gas tank? Or can you still use regular in a vehicle that calls for premium? 

That’s the question that Aeschbach Auto (@aeschbachauto), a small auto repair shop based out of Wisconsin, recently answered in a now-viral TikTok. In the nearly minute-long clip, an unnamed mechanic was asked what would happen if you fill a luxury car with low-octane fuel, or “regular” 87-octane gasoline. As of this week, his explainer clip had amassed more than 2.4 million views. 

Can you put ‘regular’ gas in a car that lists premium?

According to the mechanic at Aeschbach Auto, drivers can get away with filling their car up with regular fuel “the majority of the time.” That’s especially true, he said, if you’re just idling or cruising on the highway. 

“You can get away with it,” he said. 

However, you shouldn’t make a habit out of using regular gasoline on cars that require premium, the mechanic warned. He said that under a “heavy load,” or heavy acceleration, you might notice engine knock, which can speed up wear and tear. 

“In really severe cases,” he warned, “it could damage the engine.”

This much is true. According to The Drive, premium gasoline prevents this. The website notes that this phenomenon isn’t typically harmful to your car’s engine if regular gas fill-ups are sporadic. But that repeated engine knock can cause long-term damage to your vehicle. With older cars that require high-octane fuel, it said, your car might start knocking “before you can leave the gas station.” 

The mechanic from Aeschbach Auto said that, in most newer cars, “the computers are smart enough” to adjust their engine parameters accordingly when low-octane fuel is detected. Still, he didn’t recommend using regular gas if your car specified that it needed premium. 

“In a crunch, if you have to get gas and the place you stop doesn’t have premium gas… you can certainly fill up with 89 or 87 as long as you drive it responsibly to another gas station to fill back up with the appropriate gas,” the mechanic said.

Writers at The Drive agreed. “If your car needs premium, you probably won’t actually end up saving money using regular because you’ll go through it more quickly,” it added.

Some users aren’t buying this advice

Despite the mechanic’s warning, several commenters said that their luxury cars have worked just fine with regular gasoline. 

“Always use regular with no problems,” one user boasted.

“I’ve been using 89 instead of premium for the last 15 years on Mercedes and I had no problems,” another added. 

And some were more skeptical of the mechanic’s video.

“You save money, that’s it,” wrote one naysayer. 

While these individual anecdotes may be true, others have horror stories about what can happen if a luxury car isn’t given the right gas for its engine.

“My mom never bothered to look at the manual to see what kind of gas her car needs,” one man said. “After driving it for a couple years, one day the engine seized.”

“I’ve always used premium in my Acura and one time I had to get regular and I felt like I could notice a huge difference in performance,” another shared. 

Because of this, some luxury car drivers issued a PSA to viewers: Don’t buy a luxury car if you don’t want to pay for—or can’t afford—high-octane gas. 

“Don’t buy a luxury car if you can’t afford premium,” one user wrote. 

“Always follow the car manual,” another advised. 

The Daily Dot has reached out to Aeschbach Auto via TikTok comment.

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