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SKU: FPE-HAR-GM-NSBU-0405 | UPC: 732777409600
Fleece Performance 04.5-05 GM 2500/3500 Duramax (w/Allison Transmission) NSBU Pigtail
The Fleece Performance NSBU Pigtail replaces the factory wiring harness on 2004.5-2005 Chevrolet Silverado and GMC Sierra 2500HD/3500HD trucks equipped with 6.6L LLY Duramax diesel and Allison 1000 transmission. Corrosion at the firewall NSBU connector leads to no-crank no-start issues and transmission limp mode which this direct-fit pigtail resolves. Built with TXL cross-linked polyethylene wire and sealed Weatherpack connectors it ensures dependable signal delivery and resistance to moisture road salt and harsh conditions.
Key Features
- Plug-and-Play Installation: Matches OEM firewall connector locations for fast replacement without cutting or splicing wires.
- Corrosion Protection: TXL 18-gauge wire with high-temperature rating and weather-tight silicone seals blocks water dirt and chemicals.
- NSBU Switch Reliability: Restores neutral safety and backup switch signals to prevent starting failures and limp mode activation.
- Exact OEM Fit: Precision-engineered for 04.5-05 LLY Duramax (VIN 8th digit Y) with full Allison transmission compatibility.
- USA Made Quality: Assembled by Fleece Performance using precision-crimped terminals for consistent electrical contact and durability.
Product Notes
- Confirm your truck has Allison automatic transmission and LLY Duramax engine (VIN 8th digit Y).
- Inspect firewall connector for damage before install to ensure full repair.
- Special order item processing may take 1-2 extra days if not in stock.
Installation Notes
- Professional installation recommended.
- Disconnect negative battery cable and relieve fuel pressure before starting.
- Access pigtail at driver-side firewall transmission harness connector no special tools required.
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2004-2005 | Chevrolet | Silverado 2500 HD | Base |
| 2004-2005 | Chevrolet | Silverado 2500 HD | LS |
| 2004-2005 | Chevrolet | Silverado 2500 HD | LT |
| 2004-2005 | Chevrolet | Silverado 2500 HD | WT |
| 2004-2005 | Chevrolet | Silverado 3500 | Base |
| 2004-2005 | Chevrolet | Silverado 3500 | LS |
| 2004-2005 | Chevrolet | Silverado 3500 | LT |
| 2004 | Chevrolet | Silverado 3500 | WT |
| 2004-2005 | GMC | Sierra 2500 HD | Base |
| 2004-2005 | GMC | Sierra 2500 HD | SLE |
| 2004-2005 | GMC | Sierra 2500 HD | SLT |
| 2004-2005 | GMC | Sierra 2500 HD | WT |
| 2004-2005 | GMC | Sierra 3500 | Base |
| 2004-2005 | GMC | Sierra 3500 | SLE |
| 2004-2005 | GMC | Sierra 3500 | SLT |
| 2004-2005 | GMC | Sierra 3500 | WT |
Why Choose Fleece Performance?
- 20+ years specializing in Duramax diesel components and tuning solutions.
- High-grade materials tested for heavy-duty truck environments.
- Engineered and assembled in the USA for precise fit and durability.
Frequently Asked Questions
-
Q: Does this fit early 2004 Duramax trucks?
A: Fits 2004.5-2005 models with LLY engine (VIN 8th digit Y) and Allison transmission check VIN for exact match. -
Q: What wire and connector materials are used?
A: TXL 18-gauge wire rated for high temperatures with OEM-style Delphi Weatherpack connectors and silicone seals. -
Q: What is the warranty and install time?
A: Limited lifetime warranty against defects installs in 15-30 minutes with basic hand tools.
Shipping & Handling
- Method: UPS Ground / USPS Priority
- Availability: In stock - ships same or next business day
- Packaging: Protective padded envelope 6 x 4 x 1 inches
- Weight: 0.1 lbs
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