If you own a Malibu or Axis boat with a Monsoon M6Di engine, you may have heard about a recent update recommending a switch to 0W40 oil.

Naturally, this has raised a lot of questions:

• Do I actually need to switch?
• Is my boat affected?
• What oil and parts do I need?

👉 The good news: this is a straightforward update—and MalibuParts.com is here to help you every step of the way.

Not every boat owner is sure if this applies to them—and that’s okay.

👉 The easiest way to know is to ask us.

Chat with our team or give us a call, and we’ll quickly help you determine if your engine should be running 0W40.

All we need is:

• Your boat model and year, or
• Your HIN (Hull Identification Number)

We’ll verify everything and point you in the right direction—no guesswork.

🔧 What You’ll Need If Your Engine Requires 0W40

If your engine falls within the updated recommendation, here are the key components:

✅ 1. 0W40 dexos R Oil

👉 Mobil 1 Supercar 0W-40 Full Synthetic Motor Oil
https://www.malibuparts.com/products/mobil-1-supercar-0w-40-qt

Designed for high-performance engines like the M6Di.

✅ 2. Oil Filter (M-Series Engines)

👉 Oil Filter Cartridge – M-Series LT4
https://www.malibuparts.com/products/oil-filter-cartridge-m-series-lt4

OEM fitment for proper filtration and performance.

✅ 3. Updated Oil Fill Cap

👉 Oil Fill Cap – LT4 0W-40
https://www.malibuparts.com/products/cap-oil-fill-lt4-ow-40

Ensures the correct oil specification is clearly labeled for future service.

💡 Why the Switch from 5W30 to 0W40?

Many of these engines originally used 5W30 oil, but updated testing showed that 0W40 provides better protection in marine environments.

Benefits of 0W40 include:

• Stronger protection at higher temperatures
• Improved lubrication under heavy load
• Better long-term engine durability

👉 In short: it’s better suited for how these boats are actually used.

⚠️ Is This Something to Be Concerned About?

No—this is a preventative update, not a sign that something is wrong.

• Most engines are performing well
• This update helps avoid future wear
• It’s a quick and simple service

🛡️ Bonus: Added Peace of Mind

GM has agreed to provide each affected engine with (1) extra year of warranty coverage beyond the standard warranty timeline. The additional warranty is based on the original date of sale and specifically covers internal internal components of the engine. For further questions specific to warranty please reach out to your dealer.

🛠️ Get the Right Parts—Fast

At MalibuParts.com, we’ve made it easy to get exactly what you need—without the confusion.

• Mobil 1 Supercar 0W-40 Full Synthetic Motor Oil
• Oil Filter Cartridge – M-Series LT4
• Oil Fill Cap – LT4 0W-40

💬 We’re Here to Help

Still not sure if you need to switch to 0W40?

👉 Chat with us or give us a call and we will:

• Verify if your boat is affected
• Confirm the correct oil and parts
• Help you get everything you need quickly

Our goal is simple: make this easy so you can get back on the water.

🚤 Final Thoughts

Switching to 0W40 dexos R oil is a simple step that helps protect your engine and keep your boat running strong.

And with the right parts—and the right team behind you—you’re set for a great season ahead.