A bottle of oil pouring into a car engineIf there's one thing we've learned from YouTube, it's that no matter how dumb of an idea you can come up with, someone else has already done it and posted a video online. Have you ever wondered if you can safely substitute the motor oil in your car with Dr. Pepper? Well, someone tried it and uploaded the disastrous results for your entertainment. We've also recently watched videos showing people gleefully pouring olive oil, gasoline, milk, honey, and even Vegemite into their cars' engines. It must be nice being able to afford ruining an engine in the name of views, we mean, science.None of these substances are formulated to do the job of motor oil. Motor oil does two things: It cools, and it lubricates. It forms a thin a coat around the moving engine parts to keep them from rubbing against each other. This cuts down on wear, as well as heat from friction. To do that, oil's thickness, or viscosity has to stay the same, even in temperature extremes. Vegemite is too thick to do it. Gas isn't thick enough, and the rest of those substances change under extreme heat. They also don't contain the additives found in oil that help distribute heat, protect from rust and wear, and maintain viscosity. That's not to say that an engine won't run for a little while on some of these things, like olive oil, for instance. But none of them work as a viable substitute for motor oil. This seems like a waste of perfectly good Dr. PepperThe YouTuber who runs the Hangar Garage channel was ready to get rid of his Suzuki Swift. Most people would put it on Facebook Marketplace or trade it in. But how are you going to get views doing that? So, he drained the motor oil and refilled the engine with Dr. Pepper. Dr. Pepper can't be blamed for the final destruction of the poor little car, since he subjected it to all manner of abuse, including flipping it over with a tractor. But from the very beginning of the experiment, when the Dr. Pepper was poured into it, the car smoked like the Marlboro Man at a party and sounded like a lawn mower in pain.We're sure you don't need to be convinced that pouring soda into your crankcase is a bad idea. But the scientific reason that this is an awful idea has to do with the fact that soda is basically just water, sugar, and acid. None of those ingredients are lubricants. In fact, they can damage an engine. Sugar caramelizes at high temperatures, which would leave sticky deposits in the engine. Phosphoric acid can create flammable hydrogen gas when it comes in contact with metals. Water can cause rust, as well as make bearings quickly wear out. We've also explained why soda isn't a good substitute for coolant either. Is Vegemite good for more than being a tasty spread? (spoiler: no)The YouTube channel Garbage Time warns us with the title of its video, "NEVER use Vegemite as Engine Oil." Thanks for the warning, Garbage Time, we were just about to try that if you hadn't stopped us. Actually, we're not even sure where we would buy Vegemite this side of the equator. That video is an autopsy of an engine they destroyed in a previous video, "I replaced my oil with Vegemite." The sacrificial car was a partially wrecked AU Ford Falcon, of which, the YouTuber said, "No one will be sad to see this thing get a snoot full of Vegemite." Mineral oil was mixed with the Vegemite in order to get the paste to pour through the engine. This didn't work, though, since the Vegemite resisted mixing with the mineral oil, even in the engine while it was running.The test was hardly scientific, as they also put varnish in the gas tank and ran the engine without a radiator or water pump. But the engine did die and the subsequent autopsy led the crew to conclude that the Vegemite itself killed it, as it gummed up the works. You don't have to be a chemist to understand why Vegemite is a poor substitute for motor oil. Oil needs to circulate through the engine in order to lubricate and cool the moving parts. Vegemite is incapable of doing this, since it is a thick paste. You car should not be flowing with milk and honeyThe guys over at Car Throttle decided to throw pretty much everything but the kitchen sink into their taxi. First, they drained all of the oil out, filled it with WD40, ran it around their small dirt track for a couple of laps, and revved it for a little bit. They repeated the process with baby oil, power steering fluid, honey, and, finally, milk and honey. The car ran fine on the WD40, baby oil, power steering fluid, and even the honey, but it finally died from being too clogged up after milk was poured in with the honey.We don't recommend putting any of those items in your engine, including the ones that ran fine for a few minutes, even though one of the YouTubers quipped that they proved, "that you can run your engine on all sorts [of things] that the industry isn't telling you about." Scientifically speaking, milk is a terrible lubricant. Milk is 87% water, which isn't great to have in your crankcase. When milk gets heated up, it starts to coagulate or curdle. Boil that water away, and you're left with clumps of protein and fat, which would only clog up the engine. Honey isn't much better. It absorbs the moisture in the air and its viscosity, or thickness, varies depending on how much water it contains, which is bad for an engine that needs consistent viscosity in its lubrication. Gasoline and oil are not interchangeableThis one seems a little dangerous. And by a little, we mean a lot. The team at the Cleetus McFarland channel wanted to know what would happen if they replaced the motor oil in their old banged up Ford Crown Victoria with gasoline. At first, it wouldn't start. They speculated that was because it was flooded. They took out the air filter and disconnected the evacs in an attempt to get the car started. It did start, but then it promptly erupted in fire as the gas came out the evacs and spread all over the engine. The team put out the fire with multiple fire extinguishers, and then, because only God knows why, they started the car up again. But this time, it ran fine, at least for 17 laps around a race track before it finally died.Why is gasoline a poor substitute for motor oil? As one of the guys explains in the video, the thickness of oil provides a buffer between moving parts, preventing metal-on-metal contact. This is especially true when it comes to separating bearings from the rods and crankshaft. The crankshaft has to spin in order for the engine to produce power. He also said as the engine got hotter in the Crown Vic, the bearings started to break up since there wasn't a buffer to protect them. What about swapping motor oil for olive oil?The crew at Garbage Time substitutes motor oil with weird things — besides the Vegemite video, they also did one with chocolate. Why mess with a formula that gets views? Anyway, the main presenter at the channel owns an old FSM Niki 650, which he named "Tony." Tony has been put through a lot of abuse at the channel, including having all of his oil swapped for olive oil. How did Tony do with olive oil running through his engine? Pretty well, actually. They road tested the car for several minutes, and it never died. There was no knocking or smoke, the engine didn't overheat, and it ran smoothly. The YouTuber lamented that he would have to drive Tony every day to see how long the engine will last with the olive oil.Does this mean that olive oil or vegetable oil is a good substitute for motor oil? Of course not. As with honey, the viscosity or thickness of plant-based oils change with the temperature. In order to properly cool an engine, oil needs a consistent viscosity. Cooking oil can also get broken down by air and water, as well as by temperature. This can create a sludge in the engine.As we said, none of substances we've covered here have the additives found in engine oil that act to protect the engine. There is no substitute for the right motor oil when it comes to lubricating and cooling your engine. Want more like this? Join the Jalopnik newsletter to get the latest auto news sent straight to your inbox, and add us as a preferred search source on Google.
