Can I put 5w30 diesel oil instead of gasoline oil?

While it is technically possible to put 5w30 diesel oil in a gasoline engine, it is not recommended. Diesel oil is formulated differently than gasoline engine oil and may not provide the same level of protection and performance as the recommended oil for your gasoline engine.

Gasoline engine oils are designed to meet the specific requirements of gasoline engines, such as reducing wear and tear on engine parts, maintaining engine cleanliness, and improving fuel economy. They typically have different additive packages than diesel oils to meet the specific needs of gasoline engines.

On the other hand, diesel oils are designed to meet the specific requirements of diesel engines, such as controlling soot and improving engine durability. They are formulated to handle the high pressures and temperatures generated by diesel engines, which are different from gasoline engines.

Using diesel oil in a gasoline engine may not provide the same level of protection and may lead to increased engine wear, reduced fuel efficiency, and other issues. Therefore, it is best to use the recommended oil type for your gasoline engine, as specified by the vehicle manufacturer in the owner's manual.

While there are many products on the market that claim to clean gunk and sludge from engines, using the right oil can also help to remove build-up and improve engine performance. Here are a few types of oil that may be helpful for cleaning your engine:

High mileage oil: High mileage oils are specifically designed for engines with over 75,000 miles and contain additives that can help to break down and clean away deposits and build-up in the engine.

Synthetic blend oil: Synthetic blend oils contain a blend of conventional and synthetic oils, and often include detergents and additives that can help to remove sludge and build-up from the engine.

Full synthetic oil: Full synthetic oils are highly refined and contain a range of additives that can help to prevent and remove sludge and build-up from the engine.

It's important to note that simply changing your oil to a cleaning oil is unlikely to completely remove gunk and sludge from your engine if it has already built up significantly.

Synthetic blend and full synthetic oils are generally safe for use in high mileage cars. In fact, many synthetic oils are specifically designed for use in high mileage vehicles.

Synthetic oils are engineered to provide better performance and protection than conventional oils, especially in extreme temperatures and under heavy loads. Synthetic blend oils contain a mixture of synthetic and conventional base oils, while full synthetic oils are made entirely of synthetic base oils. Both types of synthetic oils offer superior lubrication properties, which can help reduce engine wear and extend the life of your engine.

As for oil leaks, it's unlikely that switching to a synthetic oil will cause your car to start leaking oil. In fact, some high mileage synthetic oils contain additives that can actually help reduce engine leaks by softening and conditioning seals and gaskets. However, if your car already has existing leaks, switching to a synthetic oil may cause those leaks to become more noticeable. This is because synthetic oils tend to have a lower viscosity (thinner consistency) than conventional oils, which can cause them to flow more easily through small gaps and cracks in the engine's seals and gaskets.