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Aside from fuel the most important fluid your vehicle needs is oil. This vital liquid plays a key part in keeping your engine running by lubricating metal parts, such as the pistons, to prevent premature wear. Oil also collects various particles in the engine and features detergents that break up deposits to keep your engine running smoothly.

Most motor oil isn’t designed to last very long though. The fluid breaks downs over time and isn’t able to constantly provide the necessary lubrication and protection your engine needs. You need to change it on a regular basis. Depending on the vehicle and oil, the time between oil changes could range from 3,000 to 10,000 miles. But what happens if you decide to skip oil change? The end result is that your engine won’t last as long as it could. It might also mean an extravagant bill for an engine replacement or a sooner-than-expected rebuild.

The dangers of not changing your oil

Oil will break down over time due to high temperatures in the engine (known as thermal breakdown). Because of this, the oil isn’t capable of providing the necessary lubrication for metal parts after an extended period of use. Without lubrication, the moving joints in the engine will start rubbing against each other and cause premature wear. Oil also has a limited capacity on how much particulates it can hold. By not changing the oil, particles already in the oil will begin to settle and cause corrosion.

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One of the biggest dangers of not changing your oil is sludge buildup. Sludge occurs when old oil begins to gel or solidify in an engine. When sludge begins to build up, oil isn’t able to flow freely through the engine and can cause oil starvation to crankshafts, bearings, camshafts, and other valve train components not be lubricated. In time, this can cause major damage to the engine and, in the worst situations, require an engine replacement or rebuild.

What to do if you skipped an oil change

First some bad news, it is impossible to say whether or not you have caused some sort of damage to your engine. You might get lucky and find out that nothing has happened to the engine, but more often than not some sort of wear or sludge forming has happened. The best thing to do if you’ve missed your oil change is to bring it to your mechanic immediately, tell them about what happened, and have them take a look at the engine. Even your local mechanic should be able to administer a leak down test or vacuum test. They can tell you if there are signs of incoming problems and provide a course of action to keep your engine going for the long haul.

Of course the best way to deal with this problem is to prevent it from happening in the first place. Your owner’s manual will tell you the recommend interval for when you should change your oil. The interval in the manual is only a guideline for the best of circumstances. Automakers recommend that in certain situations such as driving in a place with extreme temperatures, stop-and-go driving, or driving on dirt roads that you change your oil more frequently. Nevertheless, make sure to get your oil changed on a regular basis. It could save you from paying the big bucks for a new engine.