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Can You Break in an Engine with Synthetic Oil? (Answered)

Synthetic engine oil is more refined. These synthetic oils are more lubricated than regular oils. Regular oil is not that costly, but synthetic oils are more expensive than regular oils. As it is refined. Yet everyone uses regular oil to break in an engine. 

See If this oil can break in the engine.

Can you break in an engine with synthetic oil?

You can use synthetic oil, but the break-in period of an engine with synthetic oil is harder than with regular oil. It is considered a bad choice to break in an engine. It is finer than regular oil and causes less amount of friction. Engine break-in period may increase if you use synthetic oil.

You can use synthetic oil, but it will slow down the engine break-in time. Your engine will not provide the energy you want from a new engine. Even the performance will not be as slick as an engine that is matured perfectly. 

A new engine is not as good as a relatively old one. Like a fine wine, an engine needs to be winded up perfectly.

Another disadvantage of synthetic oil is that synthetic oils are more expensive than regular engine oils. Along with a lower fuel economy at the highest speed. A new engine needs to have strong viscosity in its engine oil. 

But synthetic oil doesn’t have the viscosity required for the engine to smooth itself up. Because synthetic oils are kept smooth intentionally. So that less friction and less engine work are required for day-to-day usage.

But the new engine demands some degrading oil to prepare itself to run smoothly in further running. Instead of all these things, synthetic oil is better as it can withstand any temperature fluctuations. 

It takes a longer time to change the oil. It can take higher loads but produces a lower amount of surface deposits.

So overall, you may use synthetic oil, as it outperforms the regular engine oil. But you should use a blend of synthetic and regular engine oils, or you should use fully regular engine oil when the engine is in a new condition. 

But nowadays, people are more prone to use synthetic oils to break in an engine. Though for first-time usage, you should use regular engine oil and synthetic oil after that.

Can you break in a small engine with synthetic oil?

Small engines can break-in with synthetic oil. But you should use regular oil first, and then you should use synthetic one. Synthetic engine oil is costly. And you will have to wait longer to have your engine break-in properly.

Although a bigger engine might need more time to break in with a synthetic engine, a smaller engine needs less time. From that perspective, we cannot recommend it, but we can say that you can use synthetic oil to break in a small engine. But it is not highly recommended.

After the break-in period, you should use synthetic oil as it will increase the longevity of your engine and increase the engine performance. However, using the synthetics earlier will not provide the benefit needed for your vehicle.

4 reasons why you cannot break in an engine with synthetic oil 

You should not break in an engine with synthetic oil for the following reasons –

 A Higher Price is Associated with Synthetic Oil:

Synthetic oil is purer and highly purified so that the engine doesn’t need to face a high level of friction, and the oil can be set there for a longer time. So, all these procedures need more cost, and the cost is included with the oil price. 

For a break-in engine oil, costly high oil is not recommended, as you must change it after some time.

The flow of Engine oil is not smooth:

After using the regular engine oil for a few days, about 500 miles, the engine becomes smoother. The piston sets itself up with the rhythm of the engine. Synthetic oil has less friction. 

For that reason, the engine takes more time to smooth itself. The flow of engine oil is not smooth initially with synthetic oil.

 New Engine needs more friction to settle:

As we said, engine oil needs more to settle. If it takes smooth oil first, it will need more energy to fix its parts. The blend of both synthetic and regular engine oil is also good. But you should use regular engine oil for a few days.

Smaller Interval Needed to Change the fuel:

Synthetic engine oil is highly costly, as we know. You need to use break-in engine oil just for 500 miles. So, if you use synthetic engine oil, you need to change it after 500 miles. That is a monetary loss. 

It is not proper value for money as you can use that oil for a small time interval. 

Does synthetic oil take longer to break in?

Synthetic oil needs a longer time to break in. Some people prefer buying reconditioned or old vehicles regarding this issue. As the engine matures and reaches its peak to perform well, people prefer those vehicles. 

Generally, a vehicle needs about 500 miles of running before reaching its break-in point. It differs from vehicle to vehicle. A bigger engine might need more time to break-in. Also, if you use synthetic oils, the engine will take a much longer period to break in. 

Engine break-in is needed so that the constant flowing of oil through its parts occurs. 

How long should you leave break-in oil in a new engine?

Regular oil works as a break in oil. This oil is not a permanent or perfect solution for your engine to run smoothly. Generally, it needs 500 miles of running before an engine reaches its break-in point. So, you should change the break-in oil after 500 miles

It is the minimum range of oil changes, but the maximum time you can leave your break-in engine oil is 1000 miles. However, after you drain your break-in oil and change it with synthetic oil, you can drive up to 7500 miles without changing the oil again.

What oil should I use for engine break-in? 

Different oil brands provide other criteria of oils to use as break-in engine oil. You can use 5w-30 or 10w-30 motor oils, including breaking additives. You can use mixed synthetic and regular oil also. Engine oil with 10% synthetic and 90% regular oil can be a good choice. 

Dedicated engine oil will make the best choice. Whatever brand you choose, you should buy 5w-30 or 10w-30 oils. Just make sure not to put 100% synthetic oil in the new engine. In 2019 about 70% of people had used synthetic oil as a break in oil. 

The number of synthetic oil for break-in engines is relatively high now. The oil manufacturers are making oils for that particular period of break-in. After using a suitable break-in oil for 500 miles, you should drain them and replace them with good synthetic engine oil.

How to break in rebuilt engine with synthetic oil?

The following steps will surely help you to break in rebuilt engine with synthetic oil –

Choose the Right Synthetic Oil:

There are several break-in engine oils available in the market. Choosing the right one for your rebuilt engine is needed. Sometimes a rebuilt engine is better than a regular manufacturing engine. 

So, choosing the right engine oil, such as 10W-40 Break-In Oil, has the optimum ZDDP level and anti-wear additives. It can be used both in racing and regular vehicles.

Vary the RPM for the First 500 Miles:

You should tune your vehicle’s RPM for 500 miles of it running. Tune the engine so that the piston and engine valves can accommodate different situations. Don’t replace the oil frequently. 

Keep the oil in the rebuilt engine at least for 500 miles and then drain it and replace it with other synthetic oils after the period is over. Remember, the rebuilt engine is heavily customized according to what you want.

Must Maintain the Manufacturers Manual:

The manufacturer of your engine must provide you a manual. Which is a written bible for your engine. Maintain every word from top to bottom. Because the manufacturer knows how to tune your engine. 

So that it becomes highly efficient and perfect, a break-in of the engine is possible by following the manual. In the manual, they will provide you with what sort of oil for lubrication your engine can take or cannot take. 

Thus maintain this manual properly. By that, your rebuilt engine will set itself up.

Final Thoughts

Use general engine oil initially. You should not use synthetic oil in your new engine that needs a break-in period. Read the vehicle’s manual first and try to follow it thoroughly. Make sure not to use break-in period oil after 500 miles. Don’t change the oil frequently during the break-in period.