The answer to this question is no. The 5w30 and 10w30 oils are not compatible with each other. They have different viscosities and they will not mix together.
Adding 10W30 to your current mix is safe and will not cause the engine to run any worse, but it also has more density than 5W30
Two oils that are similar in viscosity will mix together seamlessly. Consequently, 5W30 and 10W30 should not cause any problems in your engine.
Is It OK To Mix Different Weights Of Motor Oil?
We’ve previously written about why it may not be a good idea to mix different weights of motor oil when you are at the point of changing your car’s oil.
I’ll say a brief refresher on the concept for those of you who may have missed that post. Let’s say for example we’re talking about changing your car’s oil to vehicle type ‘X’. You have two different types, but only ever fill up at gas stations that also provide pumping service. You pull in and notice both pumps are occupied and you don’t want to delay any more than necessary, so what do you do? For starters you should try not to buy 10-weight unless it was specifically requested by the vehicle manufacturer.
Is It Bad To Mix 2 Different Engine Oils?
If you don’t know which engine oil to buy, then you might want to read this article. We will discuss the best engine oils and how they work.
If you drive a car, then you need to maintain it by changing the engine oil periodically. The problem is that there are two types of oils: synthetic and petroleum-based oils. Which one should we use?
Manufacturers produce synthetic and petroleum-based oils for different engines. Synthetic oil was created for newer cars, while petroleum-based oil was invented for older cars. When mixing them together, the car may not work properly due to incompatibility between synthetic and petroleum-based properties.
Can you switch oil type?
It is possible to switch between different types of oil. However, it is important to not mix the oils. The best way to ensure that you are using the correct type of oil is to use a qualified professional who can advise you on what type of oil your car needs.
The Bottom Line
There are many factors at hand when looking at the possible answer to this question. In short, although mixing oils is not recommended, you should use what your vehicle manufacturer advised.
No. Your engine is tuned to operate on a specific grade of motor oil. A mismatch could cause inconsistent performance, power loss and fuel economy reductions – which can add up over time. Simply put, it’s best to follow the makers guidelines if you have original equipment engine oil in your car – that way the system stays fully optimized for the machine; which will result in better fuel efficiency and greater longevity for the life of your car.