Synthetic engine oil is a manufactured variety of engine oil. It is created with a high amount of additives which makes it suitable for the environment of the engine. Synthetic engine oil is also famous for its cleaning ability.
Today, we are going to discuss and find out whether synthetic oil causes leaks or not.
Does synthetic oil cause leaks?
Synthetic engine oil is not responsible for the oil leaks inside the engine. Synthetic engine oil simply reveals the leaks by cleaning the build up of carbon deposits and the sludge on them. Switching from traditional engine oil to synthetic engine oil often reveals these leaks.
Let’s look at different types of synthetic oil and see if these synthetic oils leak or not.
Synthetic blend oil:
Synthetic blend oil is not the same as full synthetic oil. The quality and characteristic of synthetic blend oil is somewhere between the full synthetic oil and the traditional engine oil.
The components of synthetic blend oil include both traditional engine oil and full synthetic oil.
Synthetic blend oil is thinner than traditional engine oil and thicker than full synthetic oil. This means synthetic blend oil is more prone to leaks than traditional engine oil. But it does not leak as much as full synthetic oil.
This is why you will often see automobile owners switching to synthetic blend oil from full synthetic oil if there are regular oil leaks in the engine.
Synthetic gear oil:
Synthetic gear oil is a good option if you are looking for a gear oil with thinner viscosity. However, synthetic gear oil has the tendency to reveal existing leaks compared to traditional gear oil as it has a better flowing speed.
Synthetic gear oil does not cause leaks but rather reveal them by cleaning out the leaks.
Full synthetic oil:
Full synthetic engine oil is very much different from traditional engine oil. If a traditional engine was used in your engine earlier and you have recently switched to full synthetic engine oil, then you might notice some oil leaks in the engine.
Full synthetic engine oil is not directly responsible for these leaks. The cleaning ability of full synthetic engine oil often tends to reveal these leaks by cleaning them.
Full synthetic oil has a lower viscosity than traditional engine oil which means it can easily reach spots which traditional engine oil can not. So full synthetic engine oil can cause leaks to appear even without causing them in the first place.
Could switching to synthetic oil cause my valves to leak?
Switching to synthetic oil can be an indirect reason for leaks from the valves. Synthetic engine oil is known for possessing a lower viscosity than traditional engine oil.
It means that synthetic engine oil is thinner compared to traditional engine oil and therefore the supply of synthetic engine oil flows faster and better than traditional engine oil.
If there is already a leak on the valves, the synthetic engine oil will only reveal it by cleaning off the sludge from the leaks. Synthetic engine oil is not directly responsible for the leaks on your valves. People often complain about synthetic oil causing leaks in their valves.
But it is not true as synthetic engine oil is just doing its job of cleaning your engine.
Does synthetic oil make leaks worse?
It is argued that synthetic oil makes leaks worse. It is true to some extent if you consider the functions and characteristics of synthetic engine oil. Synthetic engine oil is an excellent cleaner of sludge and any kind of dirt building up inside your engine.
Synthetic oil can sometimes reveal the existing leaks on your engine by cleaning out the sludge from the leaks.
So synthetic oil can actually make leaks worse if you used to use traditional engine oil in the engine earlier. Traditional engine oil is not as free flowing as synthetic engine oil and can often seal the leaks by developing sludge on them due to their thick viscosity.
Instead of switching from synthetic oil to traditional engine oil, you should repair the leaks in the engine.
3 reasons why synthetic oil will reveal leaks
There are a lot of valid reasons why synthetic engine oil will reveal leaks more than other types of engine oil. Let’s discuss those reasons in detail.
Synthetic engine oil is a manufactured engine oil that has been made with the purpose of flowing easily through the engine. Due to its thinner viscosity, synthetic engine oil is able to reach congested places inside the engine which can not be done by traditional engine oil.
If these congested places have leaks on them, then synthetic engines will easily reveal those leaks by dripping through the leaks.
Carbon deposits and sludge:
Synthetic engine oil is better at cleaning the carbon deposits and sludge inside the engine. These carbon deposits and sludge often keep building up on the leaks inside the engine.
Synthetic engine oil is able to clean these carbon deposits and sludge which reveal the leaks in the engine.
The switching of oil:
People often face the problem of oil leaks when they switch from traditional engine oil to synthetic engine oil. When this happens, the blame goes to the synthetic engine oil. But synthetic engine oil simply does what traditional engine oil failed to do.
It flows through the engine more effortlessly and cleans the entire engine.
Synthetic engine oil even cleans the sludge made by traditional engine oil on the leaks. Traditional engine oil is not able to clean the engine and rather it makes the engine more dirty by sealing off the leaks with sludge.
Does synthetic oil swell seals?
Synthetic engine oil does not swell seals according to automobile experts. Seals can become swollen even before you use synthetic engine oil in your engine. The swollen characteristics of the seals will be revealed by the cleaning ability of synthetic engine oil.
Otherwise synthetic engine oil does not cause seals to swell. Synthetic engine oil also flows more independently because of its thinner viscosity. It is a myth that synthetic engine oil swells seals.
What causes leaks?
There can be a lot of reasons behind the oil leaks in the engine. Let’s discuss in detail about what causes oil leaks in the engine.
Faulty oil filter:
The oil filter is crucial for filtering the impurities of the engine oil. But the oil filter can sometimes become faulty due to several reasons. The list reasons include holes and cracks on the oil filter.
When the oil filter develops cracks and holes on it, the engine oil starts to leak through them. In that case, the oil filter has to be replaced immediately to stop the oil leak.
Faulty filler cap:
Filler cap of your engine can often cause oil leaks in the engine. It can become loose or get broken due to road bumps and other reasons. A loose filler cap can be fixed with bare hands. But a broken one has to be replaced to stop the oil leak.
Faulty oil pan gasket:
The oil pan gasket does the job of transferring engine oil throughout the engine. It can sometimes become faulty due to cracks and holes on them. When the gasket becomes faulty, it will cause oil leaks in the engine.
You can solve the problem of oil leak by replacing the faulty gasket with a new one.
Faulty oil drain plug:
The oil drain plug is responsible for containing the engine oil inside the oil pan. However, it can become faulty due to loose connection or holes on it. A faulty oil drain plug will cause oil leaks in the engine and will require immediate attention.
Faulty valve gasket:
The valve gasket can become faulty by developing cracks and holes on it. A faulty valve gasket will not be able to contain the oil inside the engine cylinders and cause oil leaks. It can be easily replaced to solve the oil leak.
Faulty engine seals:
The seals on your engine can become torn with holes and cracks. When the seals of the engine can no longer hold the engine oil inside the engine, it starts leaking outside through the holes and cracks.
The seals can either be repaired or replaced to get rid of the oil leak problem.
Overflow of oil:
Sometimes putting an excessive amount of engine oil in the engine can cause oil leaks in the engine. In that case, you can solve the problem by subtracting the extra amount of oil from the engine with the help of a dipstick tube.
Synthetic engine oil usually does not cause oil leaks in the engine. Synthetic engine oil can flow more effortlessly to all the parts of the engine due to its lower viscosity which often reveals the oil leaks in the engine. The leaks have to be repaired instead of switching the oil.
I am an automotive enthusiast and have been interested in cars since I was a little kid. I have worked in the automotive industry for many years and have extensive knowledge of vehicles and their engines. I am a father of two and I love spending time with my family.
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