5w40 vs 10w30 Engine Oil: What’s the Difference?

Written by

Charles Bolte


Vernon Hoppe 


Engine oil protects engine parts from wear and tear due to friction. A well-lubricated engine enables a vehicle to perform better and the parts to last longer.

There are several factors to consider in choosing the right engine oil for your vehicle. 5w40 and 10w30 are two of the most popular engine oils. This article will give you insights into these engine oils to better understand their properties and help you choose which is right.

Here’s an overview comparing 5w40 vs. 10w30 engine oil:

5w40 10w30
Suitable for modern vehicles (SUVs, light trucks, passenger cars) Ideal for truck engines and SUVs
High viscosity at lower temperature High viscosity at higher temperature
Thin oil Thick oil
Works best in the -31 °F – 104°F range Works best in the -13 °F to 86°F range
Ideal for gasoline and diesel engines Ideal for petrol and diesel engines
Full synthetic Available in these types: conventional or mineral, synthetic, and semi-synthetic


Both 5w40 and 10w30 engine oils provide the needed lubrication so your engine can function smoothly even in extreme conditions.

Without proper lubrication, the engine’s metal components, which rub against each other, become vulnerable to damage. 6.7 Powerstroke engines, for example, lack adequate lubrication, resulting in metal contamination that damages the fuel system.

While 5w40 and 10w30 engine oils have practically the same function, the key differentiating factors lie in the oil’s viscosity grades, vehicle compatibility, fuel economy, and performance level.

Differences Between 5w40 Vs 10w30

1. Oil Viscosity Grades


Viscosity indicates the consistency of an engine oil and how it easily pours at a certain temperature.

Thin oils have lower viscosity and pour easily at lower temperatures compared to thicker oils with higher viscosity.

  • Comparing 10w30 vs 5w40 engine oil as far as viscosity grade is concerned means 10w30 has a viscosity rating of 10 when cold and 30 when hot. It offers balanced protection for your engine across a wide range of temperatures and is therefore suited for use during summer and winter.
  • 5w40, on the other hand, has a cold viscosity rating of 5 and a hot viscosity rating of 40, which makes it a better choice in areas with cold winters.

2. Vehicle Compatibility


The type of vehicle is another point to consider in choosing between the two engine oils.

Both 10w30 and 5w40 are compatible with all types of vehicles.

  • But since 10w is thicker than 5w, it is better suited for more high-performance vehicles such as trucks and SUVs.
  • If you own a light truck, an SUV, or a modern passenger car, you may opt for 5w40. These types of vehicles run faster and their engines get hotter. A thinner engine oil is, therefore, more beneficial.

3. Fuel Economy


5w40 and 10w30 are both designed to deliver superior fuel economy, especially when used with compatible vehicles and engines.

  • However, 10w30’s thicker consistency resists high temperatures in cold weather. It burns more fuel to cope with the temperature.
  • 5w40 gives better fuel economy because it allows the engine to run smoothly in different conditions.

4. Performance Level


Another aspect to look into is how well and efficiently 5w40 and 10w30 engine oils perform on the road.

Both engine oils are known to deliver superior functions to secure the engine and its moving parts to help it last longer.

5w40 offers an average of 10,000 miles of efficiency while handling higher extreme conditions, whereas 10w30 gives around 5,000 miles of efficiency.

5. Pros and Cons

To better understand the advantages and disadvantages of each engine oil, here is a brief summary of factors worth considering:


  • Facilitates engine starting in cold weather
  • Reduces friction and improves engine efficiency
  • Has lower oil consumption
  • Offers more mileage efficiency
  • More environment friendly
  • Ideal for modern vehicles
  • Can be more expensive
  • Not ideal in hot climate


  • Provides better protection in extreme heat conditions
  • Effective for large, high-performance engines
  • Offers good fuel economy
  • Dynamically improves engine performance and durability
  • Better heat handling capacity
  • Ideal for older vehicles
  • More affordable
  • Can make starting difficult in cold weather
  • Can result in frequent oil changes and higher oil consumption

Which is Better?

There is a very thin line that separates 5w40 from 10w30 engine oils. Both have specific characteristics that suit particular needs, and deciding which one is better depends on many variables.

The best option is always the engine oil that can protect your engine and keep it running smoothly for a long time.

However, there are key considerations you might want to keep in mind in determining which engine oil is better for your vehicle. Here are some of them:

  • Type of engine – Knowing your vehicle’s make and model will help determine the kind of engine oil you should buy.
  • Prevailing weather conditions – If you live in a warmer area, you may choose 10w30, or opt for 5w40 if you are in a place with a colder climate.
  • Vehicle compatibility – Identify the vehicle with which the engine oil will be used, whether an SUV, a truck, a passenger car, or a high-performance vehicle.
  • Viscosity – The oil’s viscosity grade is used to measure its resistance to flow. With all other aspects considered, you can decide whether a thin or thick engine oil will work better for your vehicle.
  • Budget – You want what is best for your vehicle. Still, if the cost is a concern, you may go for the cheaper option as long as it is compatible with your vehicle and does not pose any problems.


Engine oils are designed to protect the engine and keep it in excellent running condition at all times. It can be confusing to pick the right one for your vehicle and even be a bit scary, especially for first-time car owners.

One of the most common dilemmas you may encounter is choosing between two of the most popular engine oils today. Having sufficient information on 5w40 vs 10w30 engine oils is a big step toward making the right choice.

But if you still find yourself on the fence, it is always best to go through your vehicle’s user manual and follow the recommended type for your vehicle.

5/5 - (2 votes)
Categories Oil

Magazine Latest Posts

Who Makes Quaker State Oil

Who Makes Quaker State Oil?

Have you heard about the Quaker State oil products? If yes, you might have thought ...


Is Marvel Mystery Oil Good?

  When was the last time you used a fuel or oil additive? If you ...

Predator 212 Oil Type & Capacity

Predator 212 Oil Type & Capacity

Whether used for go-karting or generating, choosing the right Predator 212 oil type & capacity ...

Quaker State vs Pennzoil

Quaker State vs Pennzoil: A Quick Comparsion

Quaker State Vs Pennzoil? Choosing the right engine oil from the same brand can be ...

How Tight Should an Oil Filter Be

How Tight Should an Oil Filter Be? How to Tighten Properly?

An oil filter is essential in maintaining the overall condition of your car engine, as ...

Is Havoline Good Oil

Is Havoline Good Oil? (Pros & Cons, Performance and More)

Havoline is a popular motor oil brand with great products that offer adequate engine protection. ...