Is it OK to mix different viscosity oils?

A vehicle cannot function without motor oil. Engine oil oils the moving components in an engine. This is to guarantee its extended lifespan and to simplify different processes. In emergencies, some car proprietors are fond of mixing different grades of motor oil. Also, you should always check for fuel in the oil

The same basic petroleum raw materials are in the composition of all mineral oils. The base oil is molecularly the same. That is why different oil viscosities will not react negatively to each other. 

Yes, you can mix the exact brand and variety of oils with distinct viscosity. Still, be aware not to mix them 50/50. Yet remember, one thing shouldn’t be mixed – if you’re concerned about the optimal oil performance. And that is different oil additive systems between brands. These things shouldn’t be mixed, be mindful of that.

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What are oil additives?

The main purpose of any motor oil is to lubricate your engine, focusing on the moving parts of the engine. It also has a protective role against corrosion, removes contaminants, prevents sludge build-up, and helps cool the engine. And this is why we need oil additives, to improve motor oil performance to its best.

What do oil additives include, and what do they prevent?

Oil additives are special chemical compounds. Their purpose is to improve the performance of the base oil. Oil manufacturers add them to improve lubrication, clean engine deposits, and prevent corrosion. Oil additives include:

  • Anti-oxidants are added to prevent thickening at high working temperatures.
  • Pour point depressants that neutralize acids formed during combustion.
  • Rust and corrosion inhibitors.
  • Detergents to reduce sludge.
  • Dispersant additives to hold contaminants in suspension.
  • Extreme pressure additives to prevent and reduce metal-to-metal contact under heavy pressure.
  • Viscosity index improvers.

The exact type and amount of these additives vary between brands. When mixing with an oil base, follow the manufacturer’s instructions to get the best performance. Different viscosities of the same brand of oil will have different amounts of viscosity index improvers.

What is more, here we come to the answer to your question from the beginning of this article:

Is it ok to mix different viscosity oils?

Yes, you can mix the same brand and type of oils with different viscosity. Yet be aware not to mix them 50/50. For example, if you mix a small amount of oil (up to 200ml) with the rest of the oil needed for your engine you will be perfectly fine. However, this is something that is not common, and please try not to make it a practice.

Can you mix 5w30 and 5w40?

Typically understood as mixing oil weights. You can blend oil weights if you need to count some oil in your car and have leftover oil. Yet, older vehicles need a distinct viscosity than newer vehicles, by all means. That said, it is advisable to try and stick to the settings from the manufacturer.

Many vehicles and trucks utilize multi-grade oil, such as 5w30 and 10w30. These specific oils can activate your motor at both cold and normal temperatures. Also, they can do that without compromising your engine’s efficacy. Multi-grade oils evolve to be thinner in cold weather. Notably, this is to provide fair protection to the engine as it warms up.

The first digit in the viscosity grade indicates low temperature. Similarly, the other figure in the viscosity grade directs to the high-temperature rating.

What to do when determining if you should mix these multi-grade oils? Well, it is best to regard the temperatures where you live and your engine’s age. This goes without saying! 

5W-30 oil is dependable in low starting temperatures. It is also dependable in hot summer temperatures (35˚C). This multi-grade oil makes less yawn on the moving engine parts and tacks. Thus, its high level of fuel efficiency.

10w30 oil is much denser than 5w30. Thus, it is better suitable for older cars as well as trucks. This oil delivers better sealing abilities needed by older engines. So, better security of the motor’s moving parts. This oil functions best at temperatures exceeding 18˚C and lower than 30˚C.

Tip: Many people want to know these days what causes orange gas. Is the contamination behind this or is there something else?

Mixing different oil brands

What about mixing additional motor oil brands? Topping up your oil level does not render any uncorrectable harm to your motor. Assembled from various companies, motor oil has a different chemical make-up. So, combining two brands for a full oil shift gap is not however advisable.

A closer reflection of the leading oil brands like Castrol, Total, or Shell will reveal that each uses special additives. Mainly to market its outcomes. Castrol Titanium, for example, arrives with a special titanium tech. This tech allows the oil to keep its thickness even under extreme temperatures.

Each brand of motor oil has various additives with various roles. Mixing synthetic motor oil with standard oil may have restricted or no effects.

Yet, what happens by combining two separate brands of synthetic engine oil? Well, the additives in both oils may react, negatively affecting your engine in the long run. Review your user manual for the most suitable type of oil that is ideal for your vehicle.

Tip: It is very useful to know how to start the car with a poor fuel pump. This can help you a lot in some cases.

Mixing regular and synthetic motor oils

More often than not, you will find motorists mixing various oil types. This is a real thing! Yet, at the gas station, you discover they do not have your typical motor oil.

The most ordinary fear for any motorist is whether mixing oils will induce a gel-like essence. To remove your fears, note that natural and synthetic oils consist of the same essential compounds.

The sole distinction is that synthetic oil is more refined, per se. Moreover, it has a huge amount of additives that can respond to each other. It’s these that guide you to the “gel” like essence you see in your vehicle.

Let’s say you are running low on oil. In that case, you should top up your vehicle with the next available oil at the gas station. Shortage of motor oil is more fatal than topping up with the incorrect fuel. Motor oil plays a major role in correctly lubricating all your motor portable parts.

Tip: There are many excellent tricks for saving fuel on the motorway. You should learn what they are just in case!

There is more to this

What if you are running low on oil? In that case, you risk these movable parts grinding against each other. Hence causing overblown friction and heat. If this persists, you will participate in full motor failure.

Motor oil also plays a critical role in heat dissipation. Chilly oil is refilled to your motor from the oil pan. There it cools some elements of the engine. This hot oil is then hauled to the oil pan, where it is chilled. This cycle assists in heat dissipation.

Note that they are some advantages you get from using pricey full synthetic oil. Factories will have some pricey additives counted to the oil to stabilize it.

Why does the pump keep stopping when I pump gas

Indications that your oil needs changing

The majority of motor oils prescribe mileage before the following oil change. Yet, you need to be on the lookout for when your oil becomes dirty. That indicates that the change of oil is critical to be able to drive your vehicle normally. Here are some signals that you are running on bad oil.

Motor noise or knocking: Oil is essential for the lubrication of portable parts. Yet, when you hear knocking sounds beneath your engine, know that the portable parts are knocking against each other.

Precisely that is causing friction. If this continues, you may incur more in restorations, by all means.

Dark motor oil

Clean and standard oil is generally amber. As it distributes through the engine’s portable parts, it picks up debris and other elements to create sludge. This directs to having an evident dark color.

You can inspect the oil color by releasing the oil dipstick and checking it. Wipe it off first, before returning it to the motor for a reasonable checkup.

Check engine light comes on

If you are quite low on oil, one of the first lights that appear is the check motor light. Yes, the light may indicate several things. Still, it is cautious you stop the car and check under your motor block for any signs of leakage.

Subsequently, inspect your motor oil levels and top up when necessary. This step you should not skip!

Tip: You should learn how to clean a fuel tank of rust. This is, by all means, critical to know how to do!

Black or dark exhaust smoke

It is completely expected to have whitish exhaust smoke. Mainly when you are driving in chilly locations. This is often because of water condensation and soon clears up as the motor warms up.

Regardless, if you see that the exhaust smoke has some blue color, what then? In that case, it could signal that your oil is leaking into your blast chambers.

This will often be attended by an oil-burnt smell. You should have this reviewed immediately. You are going to have less oil for lubrication of shifting parts.