Can I Use 5W30 Instead of 10W30?

5w30 vs 10w30

Motor lubricant is an indispensable constituent of an automobile's engine, and selecting the appropriate oil type and viscosity is pivotal for achieving superlative engine efficacy and durability.

A common question among car owners pertains to the feasibility of substituting 5W-30 for 10W-30 or vice versa.

While both oils share many similarities, they differ in viscosity ratings, which can impact engine performance in different temperature conditions. But can I use 5w30 instead of 10w30?

Let’s look at the differences between 5W-30 and 10W-30 oils and will also answer the question above.

Let’s get started!

What Do 5W30 and 10W30 Mean?

5W-30 and 10W-30 are multigrade oil types available in conventional and synthetic variants.

Their primary function is to curtail friction between engine components, thereby promoting the engine's longevity.

Being a multigrade oil type, they encompass viscosity enhancers and two viscosity grades - one pertaining to the oil's thickness at lower temperatures denoted by the numeral before the letter 'W,' which signifies winter, and the other viscosity grade indicating the oil's thickness at higher temperatures, represented by the numeral after the 'W' oil letter.

Notably, unlike single-grade motor oils, such as SAE 30, which lack viscosity index enhancers, multigrade oils possess these additives that enable them to resist thinning or thickening at higher or lower temperatures. This article analyzes how each engine oil grade performs against the other.

Can I Use 5W30 instead of 10W30?

The simple answer is yes. Undoubtedly, 5W-30 is typically a synthetic oil type for automobile engines that surpasses 10W-30 in terms of performance.

Although both exhibit equivalent viscosity at an average engine's operating temperature, 5W-30 features lower viscosity at lower temperatures, rendering it more suitable for engine startup.

However, for high-powered diesel engines, it is prudent to follow manufacturer recommendations, as the 5W variant may have higher NOACK levels, a parameter indicative of oil evaporation and emissions.

5W30 vs. 10W30

Despite belonging to the same multigrade engine oil category, these oils exhibit conspicuous dissimilarities. These differences include the following:

1. High-Temperature Viscosity

The numeral after the 'W' characterizes the oil's viscosity at an elevated temperature of 100°C (212°F), often called the ambient temperature or the engine's operating temperature. A higher numeral indicates thicker oil at high temperatures.

Despite having the same oil viscosity as an SAE 30 single-grade oil, 5W-30 and 10W-30 possess viscosity index improvers that prevent thinning in high-temperature conditions.

However, it is worth noting that their hot temperature performance may not be comparable to higher viscosity oils like 10W-40.

2. Low-Temperature Viscosity

To comprehend the oil's low-temperature viscosity, denoting anything below 0°C (32°F), one can inspect the first number preceding the 'W' in the SAE oil rating.

This number is pivotal during engine startup, particularly in colder climates with freezing ambient temperatures.

A lower number preceding 'W' implies that the motor oil is less prone to thickening at low temperatures.

Therefore, in comparing 5W-30 vs. 10W-30, the former's lower number (5) suggests that it thins out considerably in extremely low temperatures, rendering it a superior winter engine oil compared to 10W-30.

Since 10W-30 has a higher numeral before 'W,' it flows slower than 5W-30 in lower temperatures.

It is crucial to note that the SAE grades 5W-30 and 10W-30 engine oils for winter performance.

Since both possess low winter-grade oil numbers, they both exhibit low-temperature viscosities. This indicates that both types of multigrade oils perform relatively well in colder climates than other oils.

Furthermore, it is worth noting that synthetic oil formulations perform better in colder temperatures than their conventional oil equivalents due to re-engineered molecules.

3. API Ratings

The most recent iterations of SAE 5W-30 and 10W-30 motor oils are expected to satisfy all the criteria set forth by API classifications.

API classifications are an engine oil classification system or category instituted by the American Petroleum Institute. These classifications require engine oil to protect the piston against combustion residue buildup.

Nevertheless, it's vital to verify beforehand that the classification is compatible with your vehicle, as it may differ from one oil brand to the next.

4. Temperature Performance Range

As both 5W-30 and 10W-30 are classified as multigrade oils, they are designed to offer reliable performance across a broad temperature spectrum.

In particular, the 5W-30 variant is engineered to operate effectively in temperature conditions ranging from a frigid -30oC to a moderate 35oC. Comparatively, the 10W-30 variant is optimized for a narrower temperature range from -18oC to 30oC.

5. The Proper Vehicle Types

The 5W-30 multigrade oil is particularly suitable for private vehicles and light-duty petrol and diesel engines, thanks to its capacity for improved cold-temperature engine start.

Conversely, the 10W-30 oil, with a slightly higher viscosity, offers better lubrication for commercial vehicles and engine cars with heavy loads.

Although it can still function in colder temperatures, it is better suited for warmer weather conditions.

Which Is Better: 5W30 or 10W30?

In the current age of automotive engineering, it is crucial for engine oil to possess low viscosity during the startup phase.

As per the industry's consensus, 80% of the engine's wear and tear occurs during this crucial phase. The issue with using a thicker oil during the cold startup is that it fails to reach all engine parts effectively.

Since the resistance to flow is higher in such oils, they cannot lubricate all the engine's moving parts. In contrast, the 5W-30 multigrade engine oil remains viscous at 100°C but flows easier when the engine is cold.

Typically, this oil is also a synthetic lubricant known for its superior properties. However, one potential drawback of this oil is its NOACK, indicating its tendency to evaporate at higher temperatures.

5W30 Oil Characteristics

The 5W30 oil has a lower viscosity at low temperatures, rendering the cold engine startup operation much smoother. It is most effective within the temperature range of -31°F to 95°F/-35°C to +35°C (ambient temperature).

Due to its superior fluidity, this oil type promotes fuel economy and exhibits a higher propensity to thin out and flow more expeditiously at elevated temperatures. Furthermore, it offers enhanced lubrication properties over the 10W30 oil and is better suited for smaller engines and private vehicles.

5W30 oil is a more prudent option during frigid winters as it exhibits greater fluidity at low temperatures. Additionally, this oil type boasts higher fuel efficiency than its 10W30 counterpart.

10W30 Oil Characteristics

The 10W30 oil is moderately thick at lower temperatures than the 5W30 oil, making the engine startup process slightly more arduous. It is recommended for use within a temperature range of -13°F to 95°F (-25°C to +35°C).

This oil is less fuel-efficient and provides adequate engine part lubrication. It is generally utilized in commercial vehicles that have heavy-duty engines.

Moreover, the 5W30 oil can be used as a substitute for 10W30 oil in both generators and car engines.

Since both oils share similar viscosity, they perform in the same manner after attaining operating temperature, making them interchangeable.

When To Use 5W30 or 10W30?

When choosing the appropriate engine oil, it is imperative to consider its flow rate. This is because the 10W30 oil is denser when the engine is cold, resulting in slower movement than the 5W30 oil during the first engine start of the day.

Notably, these lubricants possess identical viscosity characteristics, implying that they perform identically once the recommended operating temperature is reached. Consequently, 5W30 oil can aid in faster engine startups under similar conditions.

However, avoiding oils with excessively low viscosity is crucial. This can cause the oil to splash off the engine components, causing metal-to-metal contact and reducing lifespan.

Choosing the oil with a higher viscosity level is generally the best approach to extend the life of your vehicle or generator. Nevertheless, extremely low temperatures can make 5W30 a better option.

In contrast, warmer environments are more suited to the thicker 10W30 oil. In more extreme situations, like high-temperature conditions, a thicker oil like 15W40 may be appropriate.

Most automotive and power generator manufacturers guide the appropriate oil type, indicating a safe range for your engine. This will ensure optimal engine protection for prolonged performance and optimize fuel economy, allowing for increased mileage before running low.

For temperatures above 32°F (0°C), it's recommended to use SAE 30, while temperatures below 40°F (4.4°C) and down to -10°F (-23°C) require 10W-30.

Synthetic 5W-30 can be utilized in all temperatures. Changing the oil after the first 20-30 hours of operation and every 100 hours of run time after that is advisable.

It's important to adhere to the recommended oil weight to avoid any issues that may arise.