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SKU: FPE-HAR-GM-NSBU-0104 | UPC: 732777409594
Fleece Performance 2001-2004 GM 2500/3500 Duramax (w/Allison Transmission) NSBU Pigtails
The Fleece Performance NSBU Pigtails replace the factory harness connector to the Neutral Safety Back Up switch on 2001-2004 GM heavy-duty trucks with 6.6L LB7 Duramax diesel and Allison 1000 transmission. Corrosion on the OEM pigtail disrupts TCM to ECM communication causing no crank or no start conditions and this direct replacement restores reliable starting every time. Built with premium materials these pigtails deliver long-term durability in harsh underhood environments.
Key Features
- Tinned Copper Wires: Resist corrosion and oxidation for consistent electrical conductivity over years of exposure to moisture and road salt.
- TXL Insulation: Provides resistance to heat abrasion and chemicals ensuring the harness withstands engine bay temperatures and vibrations.
- Direct OEM Replacement: Matches factory connector design for seamless fit without modifications or splicing required.
- Plug-and-Play Design: Installs in minutes by simply unplugging the old pigtail and plugging in the new one to eliminate starting failures.
- MPN FPE-HAR-GM-NSBU-0104: Engineered specifically for 2001-2004 Duramax applications to solve the most common transmission switch harness failure.
Product Notes
- Addresses intermittent no crank no start issues caused by deteriorated factory pigtail on the transmission NSBU switch.
- Inspect your existing harness for green corrosion or cracked insulation before replacement.
- Special order item expect 1-3 business days processing before shipment.
Installation Notes
- Professional installation recommended.
- Locate NSBU switch on passenger side of Allison transmission unplug factory pigtail and install new one in under 10 minutes.
- No special tools or transmission fluid drain needed includes protective conduit for added durability.
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 |
Why Choose Fleece Performance?
- Over 20 years specializing in Duramax diesel components with thousands of reliable installations.
- Manufactured with automotive-grade materials tested for extreme diesel environments.
- Precision-engineered in the USA for exact fit and function on GM heavy-duty trucks.
Frequently Asked Questions
-
Q: Will this fit my 2002 Silverado 2500HD with 6.6L Duramax and Allison?
A: Yes it fits all 2001-2004 Chevy and GMC 2500/3500 models listed with LB7 Duramax and Allison 1000 transmission confirm your setup has the NSBU switch on the transmission. -
Q: What materials are used in the pigtail?
A: Tinned copper conductors with TXL cross-linked polyethylene insulation and weatherproof OEM-style connectors for maximum durability. -
Q: Is installation DIY friendly and what warranty applies?
A: Plug-and-play install takes minutes with basic tools Fleece offers a limited lifetime warranty against defects when installed correctly.
Shipping & Handling
- Method: UPS Ground or USPS Priority
- Availability: In stock - ships same or next business day
- Packaging: Compact protective box 8 x 6 x 2 inches
- Weight: 0.2 lbs
Fleece Performance
Fleece Performance Engineering has grown from a small Indiana operation into one of the most respected names in high-performance diesel upgrades, with a product catalog built specifically around the Duramax and Cummins common rail diesel platforms that dominate the high-horsepower diesel community. Founded by brothers Brayden and Chase Fleece in a rural west-central Indiana pole barn, the company established itself as a technology leader in common rail injection systems within five years, developing the Cheetah turbocharger line and the TurboBrake electronic exhaust brake that have become standard references for what diesel performance engineering can achieve. Fleece operates from an 18,750-square-foot Brownsburg, Indiana facility capable of in-house design, manufacturing, assembly, and testing, placing them among the high-output diesel specialists who supply race teams and serious street performance builds. This collection covers Fleece Performance's full range of Duramax and Cummi...
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