It is recommended that 5w30 is used for only light-duty diesel and petrol, but also 5w30 can be managed for heavy-duty if it is used for the appropriate temperature (that is a colder climate). The 5w30 can withstand a moderate amount of pressure and extremely cold temperatures due to its high viscosity. Make sure you avoid using a high temperature and heavy-duty use for this viscosity grade oil, because this may cause cushioning and inadequate lubrication due to high pressure which will impact fuel consumption and efficiency. In terms of viscosity, conventional motor oil behaves like synthetic oil. But over time this deteriorated very fast thereby affecting the car's engine by causing low performance and fuel efficiency. 5w30 synthetic oil has more performance on the engine and is more stable, lubricates engine parts well and has better engine protection.