(Sale) FASS Drop-In Series Diesel Fuel System, 2017-2024 L5P

Part# DIFSL5P1001

$426.55 Regular price $449.00

WARNING: Cancer and Reproductive Harm - www.P65Warnings.Ca.Gov

Fits: 2017 thru 2024 Chevy Silverado/GMC Sierra 2500HD/3500HD L5P Duramax Diesel

The FASS Drop-In Series Diesel Fuel System was engineered to be the most effective filtration solution for the L5P Duramax. Backed by FASS's 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% 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. 

Installation is a breeze, usually taking 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. But don’t let the easy installation fool you—the Drop-In Series Fuel Systems offers the same world-class filtration as the Titanium Signature Series and Industrial Series lines. 

FASS's industry-leading water removal capabilities (3rd-party proven to exceed 99%) are reinforced by the unique design of the Extreme Water Separator (XWS). If the XWS reaches capacity, it acts as a dam, shutting down your truck and preventing major destruction of fuel system components. 

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.


  • 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% by removing entrained air and air vapor.
  • Extends the life of fuel injection system components.
  • Over 99% free and emulsified water separation with our Extreme Water Separator technology.
  • 2 Micron absolute filtration rating.
  • 100% drop-in, no additional modifications needed.


  • Filtration unit with filter
  • Hardware 
  • Fittings
  • Hose
  • See instructions for more information

DmaxStore Note: 

  • 2017-2019 Crew Cab Short Bed (Part# DIFSL5P1001)
  • 2017-2023 Crew Cab Long Bed (Part# DIFSL5P1001)
  • 2020-2023 Crew Cab Short Bed (Part# DIFSL5P2001)


Customer Reviews

Based on 1 review
Tanner Scott
Fass drop in & fleece all lights

Fass system is quality & don’t know if I would recommend fleece alll lights again