FASS Fuel Systems Drop-In Series Diesel Fuel System 2020-2023 GM (DIFSL5P2001)

FASS Fuel Systems Drop-In Series Diesel Fuel System 2020-2023 GM (DIFSL5P2001)
Fits: 2020-2023 Crew Cab Short Bed L5P Duramax
Part No: DIFSL5P2001 The FASS Drop-In Series Diesel Fuel System was engineered by FASS to be the most effective filtration solution for the L5P Duramax.

Backed by our limited lifetime warranty, the Drop-In Series Fuel System protects your L5P Duramax from the issues caused by fuel contamination. Without proper fuel filtration, modern diesel injection systems are prone to excessive wear, which can cost THOUSANDS!

By removing over 99 percent of the water from your diesel fuel, along with entrained air and debris down to 2 Microns, the Drop-In Series System protects the L5P's injection system from premature failure.

Additionally, by eliminating the contaminants mentioned above, our Drop-In Series System for the L5P Duramax optimizes MPG (results will vary), restores horsepower, and sharpens throttle response.

And if reliability, optimized MPG, restored horsepower, and a sharper throttle response isn't enough, this system can be installed in an hour or less! This is a true plug-and-play system, requiring no cutting, wiring, or additional modifications.

Better still, this system requires ZERO tuning changes! Whether your L5P is stock or modified, our Drop-In Series Systems will not require adjusting tunes or clearing any codes. Our industry-leading water removal capabilities (3rd-party proven to exceed 99 percent) are reinforced by the unique design of our Extreme Water Separator (XWS).

If our XWS reaches capacity, it acts as a dam, shutting down your truck and preventing major destruction of fuel system components.

FASS Drop-In Technology was developed to achieve industry-leading filtration with the simplest possible installation—making our Drop-In Series Systems a true bolt-in upgrade.

If you're mechanically inclined, a Drop-In Series Fuel System can be installed in your driveway in less than an hour! But don't let the easy installation fool you—our Drop-In Series Fuel Systems offer the same world-class filtration as our Titanium Signature Series and Industrial Series lines.

Performance Radius Cuts (PRC) are an advanced machining technique used to improve the flow of fuel through the FASS System by creating smooth-flowing cuts within the aluminum housing.

This prevents the reintroduction of air and vapor back into the fuel and prevents eddy currents from forming within the corner of a 90-degree sharp angle. FASS Drop-In Fuel Systems are the only Fuel Air Separation System that incorporates these exclusive Performance Radius Cuts, lesser competitors commonly use T-Bone and square 90-degree fittings that can limit fuel flow, cause restrictions and reintroduce air back into your fuel.
2020-2023 L5P Duramax Drop-In Series System Features:

• The only drop-in L5P filtration system that retains full functionality of the water-in-fuel sensor!
• The only drop-in L5P filtration system with air separation!
• Increases lubricity of the fuel by up to 10 percent by removing entrained air and air vapor.
• Extends the life of fuel injection system components.
• Over 99 percent free and emulsified water separation with our Extreme Water Separator technology.
• 2 Micron absolute filtration rating.
• 100 percent drop-In, no additional modifications needed.

Order processing times

Most orders will be processed in up to 72 hours. During seasonal times such as Black Friday, order processing time can take up to 5 business days. We appreciate your patience as we prepare your order.

Shipping times 

Shipment dates & lead times will vary based on product availability, product may not be in stock. If you have a question regarding availability please email or call the office to discuss lead times. By completing payment, you have acknowledged the terms and conditions stated. As stock changes daily, we do not hold inventory, first come, first serve.

Currently some brands are experience major delays - contact us or more information.

Local pickup

We currently offer free pickup from our location. You will be notified via email or phone when your item(s) are ready for pickup. 

Returns

We will accept returns within 30 days of original purchase and provide a store credit ONLY, no cash or credit card refunds will be given. All returns are subject to a 20% restocking fee. The product must still be in the original clean packaging, unused and uninstalled. We do not refund shipping and handling charges and the customer is responsible for all return shipping charges. There will be an additional rebox fee charged if the packaging needs to be replaced so please double box your returns. There is no returns of special order, tuners or custom parts.

Cancellations 

Custom parts may not be canceled once your order is placed. Cancelled Orders may be subject to a 15% cancellation fee. All returns must be pre-authorized with a Battle Born Offroad Employee and have an RGA # or they will be returned to you. Refunds will be processed within 48hrs once product is received and in original condition. Most refunds are issued to the original payment method, or by check. Please allow up to 7 business days for store credit to reflect.

Website errors

In the event a product is listed at an incorrect price due to typographical, photographic, or technical error or error in pricing information received from our suppliers, Battle Born Offroad Ltd shall have the right to refuse or cancel any orders placed for product listed at the incorrect price.

Payment processing

By clicking checkout, you agree to have your payment ran anytime after checkout. Some orders may not be charged right away, and you authorize Battle Born Offroad to charge your card up to 365 days after completing your purchase for the maximum amount you paid.

SOME ORDERS DO NOT SHIP RIGHT AWAY

Most Orders will ship within 72hrs. Some parts may not in stock and may incur a 1-52 week time due to limited availability. If you want to check the most up to date lead times on any of these products please email us at info@BattleBornOffroad.net

How can I contact you if I have questions before ordering?
You can call us directly at 702-333-0868, email our support team, or message us on our chat or on social media. We’re here to help you with fitment, installation, and product questions before you commit to a purchase.

Do you price match other retailers?
Yes, we strive to offer the best prices in town. If you find a lower advertised price from an authorized dealer, let us know—we’ll do our best to match or beat it. Some exclusions may apply for clearance or special-order items.

What is your shipping policy and how long will my order take?
We offer free or discounted shipping on most orders over $99. Orders typically ship within 1-3 business days; once shipped, standard transit times depend on your location, but generally most transit time is 2-3 days. Expedited shipping is available at checkout, and offers delivery as quick as 24hrs. Tracking info will be provided once your package is in transit and will be sent electronically to your email. 

Do you offer installation services or do you only sell parts?
Yes, Battle Born Offroad offers professional installation in our Las Vegas shop for ALL products we sell (suspension, lift kits, lighting, etc.). If you’re interested in installation, please hit our live chat button, give us a call at 702-333-0868 or email us to get a quote or get on the schedule. We can assist with shipping your vehicle to us if you are out of state and build trucks from around the country!

What warranty do your products come with?
All of our products come with a manufacturer’s warranty covering defects in materials and workmanship. Warranty durations vary by product and brand. Damage from misuse, improper installation, or off-trail abuse may not be covered. To initiate a claim or have questions, please reach out to us via email at info@battlebornoffroad.net and please submit photos, your order number and a brief description of the issue you are facing. 

Do you offer financing or payment plans?
Yes, we partner with financing providers (Affirm, Shop Pay, SNAP Finance & Koalifi) so you can pay over time. Options like “buy now pay later” or longer-term payment plans may be available. Terms and interest will depend on your credit. Affirm and Shop Pay will be shown during checkout and must be clicked during this process. Other options are offered in store or on the phone, please feel free to call us at 702-333-0868 to discuss more. 

How do you handle damages or defects in shipping?
Please inspect your package immediately upon arrival. If you notice any shipping damage, take clear photos of the damage and packaging and email us within 24 hours of delivery. We will work to make it right, either replacement of the part, or arranging return/reimbursement as needed.

Still have a question?
See all our Frequently Asked Questions or contact us with questions.