FASS DIFSL5P1001 DROP-IN SERIES DIESEL FUEL SYSTEM FOR 2017–2023 GM 6.6L DURAMAX L5P

Product Description

Upgrade your L5P the right way. The FASS DIFSL5P1001 Drop-In Series Diesel Fuel System is a true bolt-in filtration upgrade for 2017–2023 Silverado/Sierra 2500/3500 6.6L Duramax L5P. It removes entrained air, traps particulates down to 2 microns, and separates over 99% of free & emulsified water to protect injectors and the high-pressure system while improving throttle response and fuel system longevity. Backed by FASS’s limited lifetime warranty and engineered for a clean, factory-style install.

Key Benefits

• Over 99% water separation and 2-micron particulate filtration
• Removes entrained air/vapor to improve lubricity and component life
• 100% drop-in—no permanent vehicle modifications required
• Retains factory Water-In-Fuel sensor functionality

Fitment

Fits the following GM trucks (Duramax 6.6L L5P):

• 2017–2019 Chevrolet Silverado 2500/3500, Crew Cab Short Bed
• 2017–2023 Chevrolet Silverado 2500/3500, Crew Cab Long Bed
• 2017–2019 GMC Sierra 2500/3500, Crew Cab Short Bed
• 2017–2023 GMC Sierra 2500/3500, Crew Cab Long Bed

Cross-Reference / Related FASS Upgrades

• FASS FLP3000 Fleet Filter Pack
• FASS NDTSPC13250F220G No-Drop Series Plus (2017–2019, 500–900HP)
• FASS NDTSPC15250F220G No-Drop Series Plus (2020–2023, 500–900HP)
• FASS TSPC15250F220G Titanium Signature Series Plus (2020–2023, 500–900HP)

Installation Instructions

Download the official FASS Drop-In Series installation manuals here: https://www.fassride.com/manuals

FAQs

Does this kit require cutting or permanent modifications?

No. DIFSL5P1001 is designed as a 100% drop-in system for L5P trucks and installs using factory-style provisions.

Will it work with my factory Water-In-Fuel (WIF) sensor?

Yes. The Drop-In Series retains full WIF sensor functionality while dramatically improving filtration performance.

What fuel protection does it add beyond stock?

It removes entrained air/vapor to improve lubricity, filters to 2 microns, and separates over 99% of water—critical for protecting injectors and pumps on modern L5P systems.

Is tuning or other supporting mods required?

No. This is a filtration upgrade and works on stock or modified trucks without tuning.

Which FASS system should I choose if I plan future power upgrades?

For higher horsepower builds, consider pairing with a FASS No-Drop Series Plus or Titanium Signature Series Plus system sized for your target power (see related links above).

What’s Included

• FASS DIFSL5P1001 Drop-In Series assembly
• Fittings, lines, and hardware specific to L5P
• Instructions (see manual link above)

Specifications for Fass DIFSL5P1001