Is 5W-40 or 5W-30 Better for BMW Engines?

For most modern BMWs, 5W-30 is the correct and safer default choice, but 5W-40 can be better in hotter climates, for hard driving, or on certain older or high‑mileage engines—provided it still meets BMW’s official oil specifications.

Why the 5W-30 vs 5W-40 Question Matters for BMW Owners

The debate between 5W-30 and 5W-40 for BMW engines is not just about numbers on a bottle; it directly affects engine protection, fuel economy, and long-term reliability. BMW engines tend to run hot, often use turbocharging, and demand oils that meet strict standards. Choosing the wrong viscosity—or even the right viscosity but without the correct BMW approval—can accelerate wear, increase oil consumption, or affect warranty coverage.

Understanding Oil Grades: What 5W-30 and 5W-40 Actually Mean

To decide which oil is better for your BMW, it helps to understand what these grades represent and how they behave inside the engine under different temperatures and driving conditions.

What the Numbers and Letters Indicate

The “5W-30” and “5W-40” labels are viscosity grades defined by the SAE (Society of Automotive Engineers). They describe how thick or thin the oil is at cold start and at normal operating temperature.

The points below explain what each part of the label really means for your BMW engine.

• “5W” (winter rating): Indicates cold-flow performance. Both 5W-30 and 5W-40 flow similarly in cold starts, which is crucial for engine protection at startup.
• “30” vs “40” (hot rating): Describes viscosity at operating temperature (100°C). A 40-weight oil is thicker when hot than a 30-weight oil.
• Thicker when hot = more film strength: 5W-40 can provide a slightly stronger lubricating film under very high temperatures or heavy loads.
• Thinner when hot = less drag: 5W-30 typically offers better fuel efficiency and can reduce internal friction in engines designed for low-viscosity oils.

Taken together, these points show that both oils behave similarly at cold start, but diverge in their behavior once the engine reaches full operating temperature, which is where BMW’s design and usage conditions really matter.

BMW’s Official Recommendations: The Role of OEM Specifications

BMW’s own oil standards are more important than the simple viscosity grade. Modern BMW engines are engineered around specific oil chemistry and performance levels that must be respected for durability and, where applicable, warranty compliance.

BMW Longlife Specifications: LL-01, LL-04, LL-12, LL-14, LL-17

BMW uses proprietary “Longlife” (LL) oil standards that go beyond viscosity to define additive packages, high-temperature stability, and compatibility with emissions systems.

The following list outlines the main BMW Longlife specs and where they typically apply.

• BMW LL-01: Older gasoline engines (roughly early 2000s–mid 2010s); commonly used with 5W-30 and 5W-40 full-synthetic oils.
• BMW LL-04: Primarily for European diesel engines with DPFs; low-SAPS oils to protect emission systems. Often 5W-30 or 5W-40.
• BMW LL-12 FE / LL-14 FE: “Fuel Economy” oils for newer gasoline engines; usually low-viscosity 0W-20, 0W-30, or 5W-30.
• BMW LL-17 FE+: Newest-generation fuel-efficient spec, usually 0W-20 or 0W-30, for many current BMWs.
• Older pre-LL specs: Some 1990s models and early 2000s vehicles may not explicitly reference LL specs but often accept modern LL-01 oils.

These standards emphasize that the correct BMW approval on the label is just as critical as viscosity; oil that is 5W-30 or 5W-40 but lacks the right LL spec may not fully protect your engine or may not be suitable for extended drain intervals.

When 5W-30 Is Usually the Better Choice for BMW

For the majority of modern BMW owners—especially in temperate climates and normal driving—5W-30 that meets the proper BMW Longlife spec is the right choice and usually the one specified in the owner’s manual.

Engines Designed for Low-Viscosity Oils

Most turbocharged BMW gasoline engines from roughly the late 2000s onward were calibrated for 5W-30 or even thinner oils under the LL-01, LL-12 FE, LL-14 FE, or LL-17 FE+ specifications. This includes many 3 Series, 5 Series, X Series, and MINI models built under BMW’s engineering standards.

The following points summarize why 5W-30 typically remains the default recommendation.

• Factory recommendation: Owner’s manuals and under-hood stickers for modern BMWs commonly list 5W-30 as the primary grade.
• Fuel economy: Lower viscosity at operating temperature reduces internal resistance, helping efficiency and CO₂ targets.
• Turbocharger compatibility: 5W-30 flows quickly to and from high-speed turbo bearings, aiding cooling and lubrication.
• Cold climate performance: Combined with the 5W winter rating, 5W-30 maintains good cold-start protection in a wide range of conditions.
• Emission system protection: Many 5W-30 oils are formulated to meet BMW’s low-ash or FE requirements, protecting catalytic converters and particulate filters.

For late-model BMWs within warranty or running stock power levels, staying with a BMW-approved 5W-30 is usually the easiest and safest path to preserve engine health and manufacturer support.

When 5W-40 Can Be the Better Option

While 5W-30 is the default for many BMWs, 5W-40 can be advantageous in specific circumstances: high ambient temperatures, sustained hard driving, heavy modifications, or certain older engines that respond better to a slightly thicker oil when hot.

High-Temperature and High-Load Conditions

BMW engines commonly see high operating temperatures, and some drivers use their cars in severe conditions—track sessions, mountain driving, or high-speed autobahn-style cruising. In those scenarios, 5W-40 may provide an extra margin of protection.

The following situations often favor a switch—if permitted by BMW’s guidance and the correct spec—toward 5W-40.

• Hot climates: In regions with consistently high ambient temperatures, 5W-40 can better maintain viscosity at sustained high oil temps.
• Track days and spirited driving: Higher sustained RPM and turbo boost levels benefit from the stronger high-temp film of a 40-weight oil.
• Tuned or modified engines: Higher power outputs and extra heat from performance tuning can justify the thicker hot viscosity.
• Older or high-mileage BMWs: As clearances loosen and oil consumption sometimes rises, 5W-40 can reduce consumption and improve oil pressure.
• Engines originally specced for 5W-40: Certain European-market or older BMW models specifically list 5W-40 as an approved grade.

In these use cases, a high-quality synthetic 5W-40 with the correct BMW Longlife approval can help protect against shear, thinning, and varnish formation during severe use, so long as it remains within BMW’s allowed range for that engine.

The Crucial Factor: BMW Approval vs. Just Viscosity

Choosing between 5W-30 and 5W-40 is only half the story; ensuring the oil carries the proper BMW approval is equally critical. An oil can have the “right” viscosity but lack the chemical and performance characteristics BMW requires.

How to Read the Oil Label for BMW Compatibility

The front of the bottle usually highlights viscosity and marketing claims, but BMW-specific approvals are normally listed on the back label under “Approvals” or “Specifications.”

Key label elements to check before pouring any oil into your BMW are summarized below.

• Look for “BMW Longlife-01 / LL-01” or similar: For many gasoline engines built up to mid‑2010s, LL-01 is often the core spec—available in both 5W-30 and 5W-40.
• For newer engines, look for LL-12 FE, LL-14 FE, or LL-17 FE+: These are usually tied to lower-viscosity oils like 0W-20, 0W-30, or 5W-30.
• Do not rely on “BMW suitable/recommended” wording: That phrase alone is marketing; you need explicit “BMW Longlife-XX approved” on the label.
• Check for ACEA and API ratings: European ACEA specs (e.g., A3/B4, C3) often accompany BMW approvals and indicate high-performance, long-drain capability.
• Match to your manual: Your owner’s manual or BMW dealer portal will list the acceptable BMW specs and viscosity range for your specific model and engine code.

By prioritizing official BMW approvals along with the recommended viscosity, you ensure the oil’s additive chemistry, volatility, and thermal stability match what the engine was designed to use.

Regional and Model-Specific Nuances

BMW oil recommendations can vary by market, emissions rules, and model year. A 5W-30 recommended in North America might appear as 0W-30 or 5W-40 in European documentation for the same or closely related engine.

Examples Across the BMW Lineup

The correct choice between 5W-30 and 5W-40 often depends on the specific engine family and era, as well as how and where the car is used.

The following examples illustrate how guidance can differ by vehicle type and generation.

• E46/E39 era (late 1990s–mid 2000s, e.g., M52, M54, M62): Often accept LL-01 5W-30 or 5W-40; many enthusiasts and independent BMW specialists favor 5W-40 in warmer climates or on high-mileage engines.
• E9x 3 Series / E60 5 Series (N52, N54, N55): Manuals commonly list LL-01 5W-30 as primary; 5W-40 LL-01 is often used in hotter climates or for tuned N54/N55 cars.
• F-series and G-series (modern turbo engines, B48, B58, etc.): Increasingly rely on FE specs like LL-14 FE or LL-17 FE+ with 0W-20/0W-30/5W-30; 5W-40 is typically not factory-listed for these engines and should only be used if clearly permitted for your climate and use case.
• BMW diesels (M57, N57, B47, etc.): Often use LL-04 low-SAPS oils, typically 5W-30 in many regions, with 5W-40 allowed in some markets or for particular temperature ranges.
• M models and high-performance variants: Many modern M cars have very specific oil requirements; in some cases, a 0W-40 or 5W-30 LL-01 or specific “M” oil is mandated, and deviations should be approached cautiously.

Because of these variations, the owner’s manual and official BMW service information remain the final authority for your specific vehicle, with 5W-30 or 5W-40 typically being chosen within that approved framework depending on climate and usage intensity.

Practical Guidance: How to Decide for Your BMW

If you are still torn between 5W-30 and 5W-40, working through a few practical checks will usually make the correct choice clear for your situation.

Step-by-Step Decision Process

The considerations below will help you determine whether to stay with 5W-30 or move to 5W-40 while remaining within BMW’s guidelines.

1. Check your owner’s manual: Identify the recommended viscosity range and BMW Longlife spec for your exact engine and model year.
2. Note your climate: In moderate or cold climates, stick with the manual’s primary recommendation—usually 5W-30. In consistently hot climates, see if 5W-40 appears on BMW’s approved viscosity chart.
3. Consider your driving style: Daily commuting and short trips favor sticking to 5W-30; frequent track use, towing, or very spirited driving may support using an approved 5W-40 if listed.
4. Factor in mileage and condition: High-mileage engines with some oil consumption sometimes benefit from 5W-40, provided it remains within BMW’s specified range.
5. Verify BMW approval on the oil: Only use oils that explicitly state the relevant BMW Longlife approval (e.g., LL-01, LL-04, LL-14 FE) on the bottle.

By systematically following these steps, most owners can confidently identify whether 5W-30 remains the ideal choice or whether stepping up to 5W-40 offers a sensible advantage for their BMW’s real-world use.

Summary

For most modern BMWs and most driving conditions, a fully synthetic 5W-30 oil that meets the correct BMW Longlife specification is the best and safest choice. It matches the factory design for fuel efficiency, turbocharger protection, and emission-system compatibility.

However, 5W-40 can be the better option for certain older or high-mileage BMW engines, in consistently hot climates, or under severe use such as track driving—so long as the oil still carries the proper BMW approval and appears within the viscosity options allowed in the owner’s manual.

Ultimately, viscosity (5W-30 vs 5W-40) is only one part of the equation. The decisive factors are your specific BMW engine, regional conditions, driving style, and—above all—whether the oil you choose is explicitly approved to the correct BMW Longlife standard.

What happens if you use 5W40 instead of 5W30?

Putting 5W-40 instead of 5W-30 will result in slightly decreased fuel efficiency and potential performance issues, but is unlikely to cause major damage, especially in warmer climates or for older engines. The main difference is that 5W-40 oil is thicker at operating temperature, which can slightly increase friction and oil pressure. It’s always best to follow the manufacturer’s recommendation, which is found in your owner’s manual or on the oil fill cap. 
What to expect

• Slightly reduced fuel economy: Thicker oil creates more drag on engine components, leading to a small decrease in fuel efficiency. 
• Potential performance impact: A thicker oil may slightly reduce high-end horsepower. 
• Increased oil pressure: 5W-40 has higher viscosity, which can lead to higher oil pressure readings. 
• Potential benefit for older engines: A thicker oil may be beneficial for older, high-mileage engines that have increased wear and tear, as it can help maintain oil pressure. 
• No harm in cold starts: The “5W” rating is the same for both oils, meaning both will have similar flow characteristics during cold starts. 

When to be cautious

• Modern engines: Modern engines are designed with precise tolerances, and using a thicker oil can cause problems that the manufacturer did not design for, so it is best to stick with the recommended 5W-30. 
• Warranty issues: Using an oil that does not meet the manufacturer’s specifications can potentially void your warranty. 
• Stop-and-go traffic: If your engine runs hot in stop-and-go traffic, the thicker oil could be a benefit. 

Best practices

• Check your owner’s manual: The manufacturer’s recommendation is the safest guide. Check the manual for the correct oil viscosity and specifications. 
• Don’t switch for “just because”: There’s no need to switch from 5W-30 to 5W-40 unless you have a specific reason, such as a high-mileage engine or a preference for heavier oil in a hot climate. 
• Stick to a single type: If you do switch, make sure to use the new oil at your next oil change, as mixing different viscosities is not ideal. 

Is 5W-30 good for BMW?

To answer you question, the 5W-30 BMW oil will work excellent, it is full synthetic and used across most BMWs other than the M cars’ 10W-60. I’d stick to that, or if you want get a LL-01 full synthetic from Castrol, which is BMW’s supplier.

Can you use 5W40 in BMW?

SAE 5W30, 5W40. The oldest available specification. Anything with this rating has been approved for older model BMWs – all chassis before the E46 and engines before the M54.

What is the difference between 5W30 and 5W40 BMW?

For 5w40 oil:
In practice, this means that each oil is just as viscous at lower temperatures and will remain viscous at -30°C, however 5w40 oil outperforms 5w30 oils at higher temperatures, being effective up to ambient temperatures of 50°C, as opposed to 30°C.