Automotive

What Happens If You Use 10W-40 Instead of 5W-30 in the UAE?

Michel July 31, 2025

Choosing the right engine oil is crucial for your vehicle’s performance, especially in a hot climate like the UAE. Many car owners wonder whether they can use 10W-40 instead of 5W-30, especially if they find it more readily available or at a better price. However, using the wrong viscosity can have serious consequences for your engine.

In this guide, we’ll explore:

  • The key differences between 10W-40 and 5W-30

  • How the UAE’s extreme heat affects engine oil performance

  • The risks of using the wrong oil viscosity

  • Expert recommendations for selecting the best oil for your car

  • Why Nescol Lubricants is a trusted choice for high-quality engine oils

Understanding Engine Oil Viscosity: 5W-30 vs. 10W-40

Engine oil viscosity refers to its resistance to flow. The numbers before and after the “W” (which stands for “Winter”) indicate how the oil performs in cold and hot temperatures.

  • 5W-30:

    • 5W: Flows better in cold temperatures (easier cold starts).

    • 30: Thinner at high temperatures, ideal for modern engines.

    • Recommended for most newer cars, especially those with turbochargers or fuel-efficient engines.

  • 10W-40:

    • 10W: Slightly thicker in cold weather (may cause slower starts in extreme cold).

    • 40: Thicker at high temperatures, offering better protection in older or high-mileage engines.

    • Often used in older vehicles or performance engines that run hotter.

Can You Use 10W-40 Instead of 5W-30 in the UAE?

The UAE’s scorching temperatures (often exceeding 45°C/113°F) put extra stress on engine oil. While 10W-40 is thicker and may seem better for heat resistance, switching from 5W-30 without consulting your car’s manual can cause problems:

  1. Poor Cold Starts (Even in the UAE)

    • While the UAE doesn’t get extremely cold, early mornings in winter can drop to 10-15°C (50-59°F).

    • 10W-40 is thicker at startup, making it harder for the oil to circulate quickly, leading to increased engine wear.

  2. Reduced Fuel Efficiency

    • Thicker oil (10W-40) creates more drag on engine components, forcing the engine to work harder.

    • This can lead to higher fuel consumption, which is a concern with rising fuel prices in the UAE.

  3. Potential Engine Damage Over Time

    • Modern engines are designed for 5W-30 because it flows faster to critical parts.

    • Using 10W-40 may lead to inadequate lubrication, increasing wear on components like the turbocharger, camshaft, and bearings.

  4. Voiding Warranty

    • If your car manufacturer specifies 5W-30, using 10W-40 could void your warranty if engine damage occurs.

When Is 10W-40 a Better Choice?

While 5W-30 is generally recommended for newer cars, 10W-40 may be suitable in some cases:

✅ Older Engines (High Mileage) – Thicker oil can help reduce oil burn-off and leaks.
✅ Performance or Modified Engines – Some high-performance engines run hotter and benefit from thicker oil.
✅ Extreme Heat Conditions – If your car is frequently driven in prolonged high heat (desert driving or heavy towing), 10W-40 may offer better protection.

However, always check your owner’s manual before making a switch.

Best Engine Oil for UAE Conditions

The UAE’s extreme heat demands an oil that:
✔ Flows quickly at startup (even in mild winters)
✔ Resists thinning in extreme heat
✔ Provides maximum engine protection

Recommended options:

  • For most modern cars: 5W-30 (full synthetic) – Best balance of cold-flow and heat resistance.

  • For older/high-mileage cars: 10W-40 (synthetic blend or high-mileage formula) – Better sealing for worn engines.

  • For extreme heat & performance cars: 5W-40 or 10W-60 (full synthetic) – Used in some European sports cars.

Why Choose Nescol Lubricants?

When selecting engine oil in the UAE, quality matters. Nescol Lubricants offers:
🔹 High-performance synthetic oils designed for extreme heat.
🔹 Advanced additives to prevent sludge and deposits.
🔹 Optimal viscosity grades for both modern and classic cars.

Using Nescol’s 5W-30 full synthetic oil ensures:

  • Smoother cold starts

  • Better fuel efficiency

  • Longer engine life

  • Maximum protection in UAE temperatures

Final Verdict: Should You Use 10W-40 Instead of 5W-30?

Stick to 5W-30 unless your car manufacturer approves 10W-40. While 10W-40 may seem like a good alternative due to the UAE’s heat, modern engines are engineered for 5W-30, and using a thicker oil can lead to:
❌ Poor lubrication at startup
❌ Reduced fuel economy
❌ Potential long-term engine damage

If you’re unsure, consult your mechanic or check your car’s manual. For the best protection, choose high-quality synthetic oil from Nescol Lubricants, ensuring your engine runs smoothly in the UAE’s harsh climate.

FAQs

1. Can I mix 5W-30 and 10W-40 oil?

  • It’s not recommended. Mixing viscosities can disrupt oil performance. Always use the same grade.

2. Will 10W-40 damage my engine if I use it once?

  • A one-time use may not cause immediate damage, but prolonged use is risky.

3. What’s the best oil for turbocharged engines in the UAE?

  • 5W-30 or 5W-40 full synthetic (check manufacturer recommendations).

4. Does thicker oil reduce engine noise?

  • Sometimes, but it’s not a solution for underlying engine issues.

5. Where can I buy Nescol Lubricants in the UAE?

  • Check authorized dealers or their official website for distributors.

Conclusion

Using the wrong engine oil viscosity can harm your car’s performance and longevity. While 10W-40 has its uses, 5W-30 remains the best choice for most modern vehicles in the UAE. For optimal engine protection, always use high-quality synthetic oil like Nescol Lubricants, ensuring smooth performance even in extreme heat.

Stick to the manufacturer’s recommendation, and your engine will thank you! 🚗💨

Leave a Comment