# Fleece Performance 01-04 GM 2500/3500 6.6L LB7 Duramax SureFlo Performance Sending Unit PROBLEM: If you are running an aftermarket pump that is mounted external of the fuel tank, you will need to install a draw straw or drill your fuel tank to accommodate a sump. Each of these has some pretty significant drawbacks including the 1/4 tank issues that result in cavitation of the pump when you draw air into the fuel system. SOLUTION: SureFlo performance sending units are designed to work with aftermarket lift pumps and fits directly into your stock sending unit location. It features factory style quick disconnects to adapt your stock fuel lines at the tank, giving you the cleanest installation available, and requiring no cutting or drilling of the tank. SureFlo works by drawing fuel from, and returning fuel to, the bucket assembly at the base of the unit. This ensures you are always drawing fuel into your pump and not drawing air into the fuel system as well as eliminates the dreaded 1/4 tank problems. The SureFlo bucket also incorporates one way check valves to allow fuel to easily flow in at lower levels. Our SureFlo performance sending units are also a great alternative for trucks originally equipped without an in tank pump needing to repair a malfunctioning level sender or if you are simply looking to run your own custom fuel lines directly to the tank. Features OEM style fitment that requires no tank cutting or drilling New fuel level electronics and fuel float Heavy duty billet aluminum cap Universal -8 AN ports for professionally plumbing a custom fuel setup New O-ring or flange seal CROSS-REFERENCE Year Replaces GM OE Part Number 2001-2004AC Delco 89060639 APPLICATION NOTES For use on pickup style trucks only - for cab & chassis verify your pump P/N to the cross-reference table. - Universal -8 AN ports for professionally plumbing a custom fuel setup - OEM style fitment that requires no tank cutting or drilling - New fuel level electronics and fuel float - Heavy duty billet aluminum cap - New O-ring or flange seal This Part Fits: Year Make Model Submodel 2001-2004 Chevrolet Silverado 2500 HD Base 2001-2004 Chevrolet Silverado 2500 HD LS 2001-2004 Chevrolet Silverado 2500 HD LT 2004 Chevrolet Silverado 2500 HD WT 2001-2004 Chevrolet Silverado 3500 Base 2001-2004 Chevrolet Silverado 3500 LS 2001-2004 Chevrolet Silverado 3500 LT 2004 Chevrolet Silverado 3500 WT 2002-2004 GMC Sierra 2500 HD Base 2001-2002 GMC Sierra 2500 HD SL 2001-2004 GMC Sierra 2500 HD SLE 2001-2004 GMC Sierra 2500 HD SLT 2003-2004 GMC Sierra 2500 HD WT 2002-2004 GMC Sierra 3500 Base 2001-2002 GMC Sierra 3500 SL 2001-2004 GMC Sierra 3500 SLE 2001-2004 GMC Sierra 3500 SLT 2004 GMC Sierra 3500 WT ## Details - **Price:** 545.02 CAD - **Vendor:** Fleece Performance - **Type:** Fuel Systems ## Variants | Variant | Price | Available | |---------|-------|-----------| | Default Title | 545.02 CAD | In stock | ## Images - Photo - Primary - User 2 - User 3 - User 1 - User 9 - User 4 - User 1 - Logo Image --- > Source: [Standard Auto Part](https://www.standardautopart.com/products/fleece-performance-01-04-gm-2500-3500-6-6l-lb7-duramax-sureflo-performance-sending-unit) > Updated: 2026-06-27