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AMSOIL 10W-40 Synthetic Dirt Bike Oil DB40

AMSOIL 10W-40 Synthetic Dirt Bike Oil

Product Code: DB40

Premium 100% synthetic 4-stroke motorcycle oil specifically formulated for dirt bikes. DB40 delivers exceptional protection for motocross, enduro, and trail riding applications. Advanced synthetic formula provides superior wear protection, reduced friction, and extended drain intervals compared to conventional motorcycle oils.

Benefits: Maximum engine protection, reduced wear on cams and bearings, smoother shifting, cooler engine operation, extended drain intervals, improved fuel efficiency, excellent shear stability, superior deposit control.

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Why Use AMSOIL 10W-40 in Your Dirt Bike

🏍ī¸ Maximum Engine Protection

High-RPM dirt bike engines demand superior lubrication. AMSOIL's synthetic formula provides exceptional wear protection for cams, crankshaft, and transmission components.

đŸ”Ĩ Cooler Engine Operation

Reduced friction means less heat generation. AMSOIL helps your engine run cooler during hard motocross motos or long trail rides.

⚙ī¸ Smoother Shifting

Advanced friction modifiers ensure smooth, positive shifting through all gears. No more notchy or hard shifts.

⏱ī¸ Extended Drain Intervals

AMSOIL lasts 2-3x longer than conventional motorcycle oils. Change oil less frequently while maintaining superior protection.

đŸ’Ē More Power

Reduced internal friction means more horsepower reaches the rear wheel. Feel the difference in acceleration.

💰 Better Long-Term Value

Extended drain intervals and superior engine protection mean lower maintenance costs and longer engine life.

Purchase Options

Best Value
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Preferred Customer

Wholesale pricing with 25% discount

  • ✓ 25% off retail pricing
  • ✓ Free shipping on orders $100+
  • ✓ No minimum order requirements
  • ✓ Auto-ship discounts available
  • ✓ 15% off first order
$15

/ 6 months

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Retail Purchase

Standard retail pricing

Standard retail pricing for one-time or occasional purchases. No registration or commitment required. Perfect for trying AMSOIL products or buying specific items as needed.

  • ✓ No registration required
  • ✓ Order anytime
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Commercial Account

For fleets and businesses

Business purchase option for fleets and commercial operations. Ideal for construction companies, farms, government fleets, and equipment managers who need bulk pricing and dedicated support.

  • ✓ Volume pricing
  • ✓ Dedicated support
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Retail Store Account

Sell AMSOIL in your store

  • ✓ Stock products on your shelves
  • ✓ Retail markup pricing
  • ✓ Marketing materials provided
  • ✓ Ideal for powersports shops
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Dealership Option

Become an AMSOIL Dealer

  • ✓ Wholesale pricing
  • ✓ Earn commissions
$100

/ year

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Secure Payment

We accept Visa, Mastercard, American Express, Discover and PayPal, and provide secure checkout and encrypted payment processing.

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Easy Returns

We offer easy returns for customers. If your product is unused and unopened, you may return it within 30 days for a full refund of the purchase price.

View full AMSOIL Return Policy

Rider Testimonials

See what dirt bike riders are saying about AMSOIL 10W-40 Synthetic Oil.

"Switched to AMSOIL DB40 in my CRF450R and the difference is night and day. Engine runs noticeably cooler after long motos, and I'm getting smoother shifts. Been running it for a full season now with zero issues. Won't go back to conventional oil."

— Mike R., Motocross Racer

"I ride hard enduro trails in West Virginia. AMSOIL has never let me down in my KTM 450EXC. Extended drain intervals are a huge plus when you're out on the trail all day. Engine protection is top notch even in extreme conditions."

— Sarah K., Trail Rider

"Run a small shop and we've been using AMSOIL in all our customer bikes for 2 years. Fewer comebacks, happier customers, and the extended drain intervals mean less waste oil. Joe's service and pricing make it easy to recommend."

— Dan T., Shop Owner

Frequently Asked Questions

Common questions about AMSOIL 10W-40 Synthetic Dirt Bike Oil.

How often should I change oil in my dirt bike?

With AMSOIL synthetic, you can extend drain intervals significantly compared to conventional oils. For most riders, 10-15 hours is typical. Severe conditions (racing, extreme dust) may require more frequent changes.

Will AMSOIL void my warranty?

No. AMSOIL meets or exceeds all major motorcycle manufacturer specifications. The Magnuson-Moss Warranty Act protects your right to use aftermarket oils that meet OEM specs.

Can I use DB40 in my street motorcycle?

Yes, DB40 works great in street bikes too. However, AMSOIL offers specific motorcycle oils for street use with different additive packages optimized for longer drain intervals.

What's the difference between DB40 and DB50?

DB40 (10W-40) is ideal for normal to hot conditions. DB50 (10W-50) provides better protection in extreme heat or for high-performance racing applications. Check your owner's manual for recommendations.

Does AMSOIL work with wet clutches?

Yes, AMSOIL dirt bike oils are specifically formulated for wet clutch compatibility. You'll get smooth clutch engagement without slipping or chatter.

Need help choosing the right oil for your bike?

Call or text us at (763) 213-9163 or use the AMSOIL product lookup tool. We'll help you find the exact oil for your make, model, and riding style.

Questions? We're Here to Help

Call or Text: (763) 213-9163

Email: amsoilsyntheticoilproducts@gmail.com

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What Our Customers Say

Read real reviews from dirt bike riders who trust AMSOIL for their off-road motorcycles

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