Do you have some leftover 10W30 engine oil and planning to mix it with 5W30 to save some bucks? Will it be a good decision for your engine? Can you mix 5W30 and 10W30? Yes, you can. mix 5W30 and 10W30. But it isn’t necessarily ideal as both oils flow at different rates due to their different temperature endurance.
Basically 5W30 grade engine oil perform well at low temperature and 10W30 at medium temperature. If you need to mix 5W30 and 10W30 in an emergency, use some additives and put the lighter one first.
- Can you Mix 5W30 and 10W30?
- Potential Consequences of Mixing 5W30 with 10W30 Engine Oil
- Can you Put 10W30 instead of 5W30?
- Difference between 5W30 and 10W30
- Design Purpose
- Precautions to Follow while Mixing 5W30 and 10W30
- Can you mix 10W30 and 10W40?
- Can you mix synthetic oil with regular oil?
- Is 5W30 or 10W30 better for summer?
- Final Words
Can you Mix 5W30 and 10W30?
If your car’s manufacturer recommends 10W30, you can mix some 5W30 engine oil on it. In warm climates, the mixture of 5W30 and 10W30 will act quite similar since both have the same viscosity at operating temperatures.
But if your car manufacturer recommends 5W30, using this mixture won’t pump properly at very cold temperatures. If you’ve already mixed 5W30 and 10W30 as an accident or as a result of outright ignorance, don’t worry. Your engine will survive till the next oil change.
However, you mightn’t get the desired output by mixing these two oils. 5W30 engine oil is lighter and has less density while 10W30 is a higher grade and has more density.
One common purpose of planning to mix 5W30 and 10W30 is to get thicker oil. But mixing 5W30 and 10W30 will still provide you a 30 weight at operating temperature. So this experiment won’t be helpful. Instead, you can mix 10W40 with the 5W30 following a 50-50 ratio to get thicker oil.
Potential Consequences of Mixing 5W30 with 10W30 Engine Oil
Mixing 5W30 and 10W30 won’t hurt your vehicle immediately but can reduce the engine’s performance and shorten the oil-changing interval.
The reason is that these oils have different additives which won’t let them blend properly. Using a mixture of 5W30 and 10W30 can also affect the proper flow during the cold season.
10W30 engine oil is also thicker than 5W30, making it better for carrying heavier loads and use during colder temperatures. But in warmer climates, thinner oil like 5W30 is more beneficial as it can provide more lubrication. But mixing these two grades won’t let them do their job properly.
The 5W oil has a different hydrocarbon molecular structure than the 10W type. So if you mix 5W30 with 10W30 engine oil, it’ll cause out-gassing. The hydrogen’s out-gassing can dry out the engine’s valve seals and collapse the hydraulic lifters.
Warranty is another crucial consideration. If your car’s manufacturer suggests using only the 5W30, they’ll void the warranty if they notice different grade oil in the engine.
Can you Put 10W30 instead of 5W30?
If you add a little amount of higher viscosity oil than the recommended, nothing should happen to the engine. The crankcase’s engine oil won’t be affected. But if you replace the recommended 5W30 with the 10W30, it’ll reduce the engine’s longevity and increase the wear of some expensive components. This change will also slightly reduce the car’s miles-per-gallon performance.
Modern car engines are designed to accept particular lubricants. A modern engine with chain tensioners and a VVT system needs specific oil pressure to run properly. 5W30 engine oil is a good option for an area with 100F ambient temperature. Though 10W30 won’t cause any problem in 100F+ weather on a cold start, it won’t benefit the engine as well.
Instead, you can notice a bit of cam phaser noise in the car engine on cold starts as 10W30 can take slightly longer to reach the engine’s top than 5W30.
If you accidentally put some 10W30 on an engine that suits 5W30, keep driving till the next oil change. In this case, you’ll have some quarts of 5W30 and a quart of 10W30 they never mix.
So don’t use an oil that has different viscosity and stick to the oil that is specified by the manufacturer.
Difference between 5W30 and 10W30
Below we’ve discussed some key differences between 5W30 and 10W30 engine oil to help you realize the effect of mixing or using one instead of the other:
Both grades of oil are similar in terms of their second number. But the difference is in the first number before W. At below-freezing temperature, 5W30 engine oil will be thinner than 10W30 engine oil.
5W30 oil is intended to work effectively at 30 to 35°C. so this oil is perfect for the area where temperatures rise too high in the summer and drop too low in the winter.
10W30 grade oil is designed to work effectively at 18 to 30°C in high temperatures.
10W30 is higher viscosity oil and flows slower at low temperatures compared to 5W30. 10W30 engine oil provides the same protection as the 5W30 to the engine parts. Both 5W30 and 10W30 engine oil have same viscosity. But 5W20 and 5W30 engine oil have different viscosity.
Still, high-speed oil is a better sealant ad offers more effective lubrication to the engine’s critical parts. Conversely, more viscous oil forces the engine to work harder to complete the task and causes higher gasoline consumption.
Though multi-grade oils can act effectively in any climate, 5W30 engine oil is thinner, making it ideal for extremely low temperatures. So 5W30 oil will provide better performance during the winter season. It’ll flow properly even at -22°F temperatures.
10W30 flows more effectively in high temperatures, making it suitable for use during summer. 10W30 engine oil will work until 0°F temperature.
Since the 5W30 oil is thinner, it helps a car start easier and quicker during cold weather. It is also a more versatile oil for any season use, thanks to its wider temperature spread. Conversely, 10W30 engine oil provides better protection to the engine parts against wear during cold weather.
Both engine oils have the same single-grade 30-weight oil base and friction modifiers to flow smoother at winter temperatures. However many people believe that 10W30 oil has more oil and less polymer, making it better than its counterpart.
Precautions to Follow while Mixing 5W30 and 10W30
Mixing two different types and viscosity oil like 5W30 and 10W30 require extra care and consideration. If you mix two wrong types or can’t mix the right type properly, you’ll experience poor engine performance, shorter oil change intervals, or expensive repairs. Follow these tips to mix 5W30 and 10W30 seamlessly:
- Don’t try to mix synthetic and conventional engine oils as one is artificially synthesized while the other one is extracted from crude sources. Mixing them can cause a gummed-up situation which is harmful to a motor and other functioning parts.
- You can mix either two light or two heavier oil. Mixing two different weights of oil won’t let you drive efficiently and cause various mechanical issues.
- Before mixing engine oils, make sure they are suitable for the current season. If you want to mix 5W30 and 10W30 oil opt for them from the same brand.
- Oil additives help to mix two different types of oil properly. It also helps the heavier fluid to move quickly and mix with lighter oil. Oil additives offer extra protection to the engine against wear. So you can use some oil additive before mixing 5W30 and 10W30 engine oil.
- To mix and homogenize 5W30 and 10W30 properly, firstly pour 5W30 oil into the engine and then add 10W30. Avoid spilling during mixing the oil as it can make a burning scent. Start the engine and run it for a few minutes to mix the oils perfectly while ensuring optimal performance.
- After mixing 5W30 and 10W30 engine oil and driving for a while, check the engine’s oil level. If you notice insufficient weight inside of the engine, mix more oil. The oil must reach enough weight according to the car’s manufacturer’s recommendation.
Also Read: Car Shaking after Oil Change
Can you mix 10W30 and 10W40?
If you aren’t in an emergency, don’t mix 10W30 and 10W40 engine oil. Though these oils perform the same during cold startup, 10W40 is a bit thicker than 10W30. So the mix won’t perform well in high temperatures. However, in moderate weather, the mixture will work fine.
Can you mix synthetic oil with regular oil?
Yes, you can occasionally mix synthetic oil with regular oil and it shouldn’t damage your engine. Since Synthetic oils provide better protection than regular oil, you won’t want to reduce its performance due to some bucks.
Is 5W30 or 10W30 better for summer?
Both 5W30 and 10W30 engine oil have higher temperatures, making them suitable for summer. However, 10W30 is a bit thicker than 5W30.so it’s preferable for warmer climates. If 5W30 is an acceptable grade for your engine, you shouldn’t replace it with 10W30 for summer use.
Many car owners ask can you mix 5W30 and 10W30 engine oil as they have some leftovers. When it’s come to the safety of expensive parts like engines, you should stick to the manufacturer’s suggestion. Though you can mix 5W30 and 10W30 for emergencies, it isn’t a good practice. So forget about the leftovers and only use the particular type and weight of engine oil recommended for your car’s engine.
Yes, it is perfectly safe for you to mix 5W-30 and 10W-30 engine oils. Thanks to their close viscosity, mixing the two oils will have no damaging effect on the engine. It's worth remembering that 10W-30 has more density than 5W-30, so make sure you pour an appropriate amount when mixing.What happens if I mix 5W-30 and 10w30? ›
They will mix perfectly. In warm climates, they will act very similarly. Both are the same viscosity at operating temperatures.Is it OK to mix different weights of motor oil? ›
Typically, it is not a good idea to mix oils, though you may be able to get away with it if the grades are fairly similar (such as using a 30 grade when a 40 grade is recommended). You should never mix conventional oil with synthetic oil.Is it OK to switch from 10w30 to 5W-30? ›
According to API motor oil guide , If you are using 10W–30, you can safely switch to 5W–30 (in car engines). 5W–30 is thinner than 10W–30 when cold. (you must follow the manufacturer's recommendations). However, switching from 5W–30 to economical 10W–30 is not always recommended.Can I use 10w30 instead of 5W-30 for high mileage? ›
You can use 10w30 instead of 5w30 as long as the vehicle isn't subjected to cold temperatures for an extended period of time. You want the oil to be pumped throughout the engine as quickly as possible after starting the engine to prevent “cold start damage”.What happens if you mix 5W and 10W oil? ›
Thanks to their close viscosity, mixing the two oils will have no damaging effect on the engine. It's worth remembering that 10W-30 has more density than 5W-30, so make sure you pour an appropriate amount when mixing.Does it matter if you mix engine oils? ›
Yes. If it's something you do only occasionally, mixing shouldn't damage your engine. Let's say you want to top off your oil, just to keep you rolling until your next regularly scheduled maintenance check. Mixing is alright, if the oil you use is the weight (or viscosity) recommended in your owner's manual.Is it bad to mix 2 different engine oils? ›
What Happens If You Mix Two Engine Oils? Technically speaking, mixing engine oils doesn't cause any harm to your engine, providing you follow a few simple rules of compatibility.What happens if you use the wrong weight motor oil? ›
Thicker oil may not flow quickly enough
Its lower viscosity allows it to flow faster and fill the tiny clearances between parts, leading to a durable, consistent lubricating film. Not only that, but the engine will waste energy pumping the thicker oil, reducing fuel economy.
Many older, high mileage engines might face issues with oil pressure due to age and wear and tear. In this case, a practical method to improve oil pressure is to use a thicker oil, since the thicker oils have heavier base weight oil, which can help protect worn engine bearings well.
The five and 10 digits refer to the viscosity at cooler temperatures. So, that means when you are comparing 5w30 vs. 10w30, the thinner 5w30 will circulate quicker, and flow through bearing tolerances better during an engine startup in the winter or colder climates.Is 10W30 better for high mileage? ›
10W-30 motor oil makes for a decent high-mileage oil. It gives a better fuel economy and oxidation resistance while reducing the oil consumption for older engines.Is 5W-30 or 10W30 better for summer? ›
Answer: There is absolutely no need to switch to 10W-30 motor oil in the summer if 5W-30 is an acceptable grade for your engine. While some car manufacturers still advocate the use of 10W-30 (or even 10W-40) as an appropriate engine oil option for summer use, it is completely unnecessary.How many miles is 10W30 good for? ›
Answer: If your car uses conventional motor oil, such as 5W30 or 10W30, we recommend changing the oil every 3,000 miles or 3 months. If your car uses synthetic oil, we recommend an oil change every 5,000 miles or 6 months.Is 5W-30 better for high mileage? ›
Pennzoil High Mileage SAE 5W-30 Motor Oil is engineered for cars that have accumulated more than 75,000 miles, particularly those that are experiencing oil leaks and oil burn off. Engines with higher mileage tend to experience more wear than new engines.Is 5W-30 good for hot weather? ›
5w30's viscosity range means it can lubricate, seal, and protect an engine's internal components in a range of climate conditions. This ability to function well both in summer and winter brings with it the convenience of not having to change oil weights with the seasons.What happens if you mix different engine oils? ›
Can oils of different grades be mixed? The good news is that mixing different types of oil it will not harm your engine in any way in the short run. Most synthetic and semi-synthetic engine oils are based on regular oil and are compatible.Can you mix 10w 30 with synthetic oil? ›
Yes. There is no danger mixing synthetic and conventional motor oil. However, conventional oil will detract from the superior performance of synthetic oil and reduce its benefits. In this post, we'll also look at if it's safe to use regular oil after synthetic oil.Will it hurt my car if I use 10W30 instead of 5w20? ›
While using it temporarily in a pinch likely won't cause your engine lasting harm, remember that the engineers who built your engine did so with a specific viscosity oil in mind, meaning it's best to stick with it. Some automakers do recommend different viscosities of oil depending on weather conditions.Why can't you go back to regular oil after synthetic? ›
Once you go to synthetic oil, there is no turning back. By nature, synthetic oil is far slick than regular oil, which means that it can result in leaks in a conventional engine (which are dangerous and expensive).
Adding oil instead of an oil change at this point could cause engine issues. This used oil needs to be removed to allow new oil to lubricate your engine's parts. PRO TIP Drop a drop of the used oil on the surface of water. New oil will bead up due to interfacial tension.What are the disadvantages of synthetic oil? ›
A few disadvantages of synthetic oil to be aware of include: Probably the most glaring downside of synthetic oil is the cost. The price of synthetic oil is around two to four times the price of conventional oil. Synthetics may be more prone to additives precipitation during cold storage conditions.What happens if you use synthetic blend instead of full synthetic? ›
Full synthetic oil offers longer oil change intervals and prevents sludge formation in your engine. However, synthetic blend oil is more affordable, can withstand extreme temperatures, and works well for heavy-duty use. Therefore, it's often recommended if you're driving a Hyundai SUV or perform frequent tow jobs.How long does synthetic oil last? ›
If you own a car that runs on synthetic oil, you're probably wondering, “How often do you change synthetic oil?” Depending on the type of car you have, most synthetic oils last between 7,500 miles and 15,000 miles. However, you'll need to check your owner's manual for more specific figures.Can two types of oil mix? ›
Yes, you can safely mix one brand of oil (e.g. Mobil 1) with a different brand (e.g. AMSOIL) or conventional oil with synthetic oil (in fact, that's what a synthetic blend is). Most synthetics today are fully compatible with conventional oils and can safely be mixed.What oil is best for older engines? ›
Monograde oils are still widely available, primarily because they're used in very hot climates, or in heavy-duty applications such as mining or construction equipment. These single-grade oils can be used in 1950s and older cars – generally SAE 30 to SAE 50 – but most owners use multi-grade.Should I use thicker oil in a high mileage engine? ›
A: Yes. This is a practical method to improve oil pressure in an older, high-mileage engine. The slightly thicker oil film from the heavier base weight oil — 10W — can help protect worn engine bearings as well.Why not to use high mileage oil? ›
High-mileage engines have common problems like wider gaps between components due to increased wear, the aging of seals and gaskets, which results in loss of elasticity and partial degradation, coking, and the build-up of carbon.How do I stop my engine from burning oil? ›
- Check for leaks regularly. ...
- Use the correct oil grade. ...
- Follow the recommended oil change interval. ...
- Avoid excessive idling. ...
- Drive responsibly.
Synthetic oils will enhance the engine protection in older vehicles with higher mileage, just as they do for new engines.
5w 20 and 5w 30 engine oils are commonly used in colder temperatures. However, they are recommended for older engines and light-duty use. This is because an oil with a higher rating indicates that it is thicker and suits well those engines which run hot easily.What does the W stand for in oil? ›
The first number precedes the letter 'W' which stands for Winter. This measurement is related to how an oil flows when it is cold, such as at engine start-up. The second number is defined by how an oil flows at normal engine operating temperatures. The smaller the number, the better it will flow.What cars use 5w-30 oil? ›
- Most popular oil for modern road cars and light trucks, as specified for most late-model BMW, General Motors and Nissan vehicles.
- Suitable for VW/Audi 502.00/503.01/505.01-99, BMW LL-01 and Ford WSS-M2C946-A.
- Thicker oil film at operating temperature than a petroleum 10W40.
The Cons of 10W30 Oil
This is mainly due to the fact that it's not as thick or viscous as SAE 30. Because 10W30 motor oil doesn't have the viscosity of SAE 30, it doesn't offer quite as much protection for older engines. So, if your lawnmower or generator is getting up there in age, SAE 30 may be a better choice.
That said, you can still use 10W-30 motor oil in warm weather. But be aware that as it's a thinner oil, it might not lubricate engine parts as well as 10W-40 as temperatures continue to increase.Is 10W30 for summer or winter? ›
These oils were straight grade oils. A 10W flows well in cold weather, to protect the engine at start up, but it's is too thin for use in the summer. A 30 grade oil, thick enough to protect in the heat, was recommended for summer use.What is the best oil to run in the summer? ›
As a general rule, you'll get the best protection in the summer when you use a slightly thicker grade of oil, such as a 10W30 instead of a 5W30. Engines need a thicker oil in the summer months because of the summer heat and its effects on thinning the oil out.When you live in a cold climate is it usually better to use 5W-30 or 10W30 motor oil? ›
The difference, though, is in the first number—the “5” or “10” before the W. This means at below-freezing temperatures, 5W30 is generally thinner (flowier) than 10W30. They also differ in their lowest operating temperature. 5W30 will still flow at temperatures as low as -22°F, while 10W30 will only work until 0°F.What motor oil is best for summer heat? ›
Full Synthetic motor oils in SAE 0W-20, SAE 5W-20, and SAE 5W-30 are designed to handle high internal temperatures, as well as the added external heat from summer road trips.What is 10W-30 oil recommended for? ›
Mobil 1™ 10W-30 is recommended by ExxonMobil for all types of modern gasoline-powered vehicles, including high-performance turbocharged, supercharged, multi-valve fuel injected engines found in passenger cars, SUVs, light vans and light trucks.
However, engine oil also degrades with time, so it's just as important to change your oil when the time-based interval has been reached. The general recommendation is to change your oil every 3,000 to 5,000 miles or every three to six months, with twice a year being the minimum.What happens if you don't change your oil for 2 years? ›
When oil has not been changed for a long time, it will begin to gel or solidify in an engine, eventually turning into sludge. When this happens, the oil will not be able to reach all parts of the engine, leading to oil starvation in the crankshafts, bearings, camshafts, and other valve train components.Can I use 10w30 instead of 5W-30 in high mileage? ›
You can use 10w30 instead of 5w30 as long as the vehicle isn't subjected to cold temperatures for an extended period of time.At what mileage should you start using high mileage oil? ›
Who needs high mileage oil? Cars with more than 75,000 on their odometer can usually benefit from high mileage oil. Older vehicles with fewer miles can benefit too, as engine seals can erode over time regardless of mileage. Degraded seals mean leaking oil, and leaking oil means your engine isn't working at its best.What is 5W-30 best for? ›
Generally, 5W-30 motor oil is recommended for gasoline and light-duty diesel use. However, 5W-30 oil can handle heavy-duty use in the appropriate climate (colder temperatures). It can withstand any cold temperature and moderate pressure in winter due to its lower viscosity.Can I switch from 5W-30 to 10w30? ›
Yes. 5w30 and 10w30 are both 30 weight oils and the exact same thickness in your engine when it is at operating temperature.What is the best engine oil for hot country? ›
In tropical weather, most OEMs still recommend multi-grade products, such as SAE 15W-40, because the lubricant flows faster through the engine than a pure SAE 40 even at higher ambient temperatures. Another important consideration when choosing an engine oil is the quality certification or performance level.How long can you use 5W-30? ›
Provides proven protection for 20,000 miles between oil changes - guaranteed.What's the difference between 5W-30 and 10W30 oil? ›
5w30 oil has a lower viscosity than 10w30, making it slightly thinner. The lower viscosity makes 5w30 a better choice in cold weather. Viscosity is the level of a liquid's resistance to flow. Thin liquids that flow easily, like water, have low viscosity.Can you mix 5W-30 and 10W30 reddit? ›
Lol you can mix them. Now in modern engines that have super thin oil requirements, yea dont dump in 10-40 into 0-20 but a 90s truck and the fact that both 5 and 10w-30 are both approved oils for that engine its fine.
No – you shouldn't mix engine oils with different specifications like this. These two oils have contrasting viscosities and are designed for completely different types of use.Is it OK to mix 5W-30 and 5W 40 oil? ›
Can You Mix 5W30 with 5W40 oil? This is a common question that many people have. The answer is yes, you can mix 5w30 engine oil with 5w40 engine oil as long as the weight of the 5w30 engine oil is greater than the weight of the 5w40 engine oil.Is 10w30 better than 5W-30 in summer? ›
Answer: There is absolutely no need to switch to 10W-30 motor oil in the summer if 5W-30 is an acceptable grade for your engine. While some car manufacturers still advocate the use of 10W-30 (or even 10W-40) as an appropriate engine oil option for summer use, it is completely unnecessary.Is 10w30 better for high mileage? ›
10W-30 motor oil makes for a decent high-mileage oil. It gives a better fuel economy and oxidation resistance while reducing the oil consumption for older engines.Can you top up engine oil with different brand? ›
You can add any engine oil as long as it has the right specifications — preferably with an official approval of the OEM (Original Equipment Manufacturer). Not the brand, but the specification and viscosity indicated in your car's manual are your reference for using the right oil.What happens if you mix SAE 30 and 10W30? ›
Technically, you can mix SAE 30 oil and 10W30 oil, but it's generally not advised to do so. Because of the differences in the two types of oil, it's possible that blending them could damage the motor of your lawnmower or generator.Can you mix 10W 30 with gas? ›
Can you use 10W-30 oil and gas in a 2-stroke engine? Of course you CAN! But it is far from the correct lubricant in a 2 cycle engine. SAE 10W-30 is far too “Thin” to provide protection in a 2 cycle engine and it also contains the wrong type of additives that will cause ash deposits and possible plug whiskering.Why is it recommended to use 5W-30 oil during winter and not 10W-40? ›
The second number is the high-temperature viscosity rating, measuring how well the oil protects you engine in those conditions. So, a 5W-30 or 0-W30 will give better protection in winter weather than, say, a 10W-40 or a 20W-50, while still providing solid high-temperature protection.What happens to an engine if I use 10W-40 instead of 5W-30? ›
What happens if you use the wrong engine oil? By mistake, we put 10W40 instead of 5W30. Nothing catastrophic, the engine won't explode the moment you turn the key. HOWEVER, with the oil being too thick the engine won't have adequate protection and it'll wear out faster (especially the bearings).What happens if you put 5W-30 oil in a 5W 20 engine? ›
Most car engines are designed to handle 5w20 oil because this type of oil flows well when the engine reaches its operating temperature of 212 degrees. If 5w30 oil is used, the engine will encounter much more resistance at this stage which is not good for it.