Ignition Lock Cylinder Switch Housing For Chevy Silverado GMC Sierra 03 To 07

This Ignition Lock Cylinder Switch & Housing is a complete key cylinder and ignition switch assembly compatible with 2003-2007 Chevy Silverado and GMC Sierra models and matches OEM Part# US-578L.

Product Overview

This ignition lock cylinder switch and housing assembly restores reliable vehicle starting and security for your Chevy Silverado or GMC Sierra. It combines the mechanical key tumbler with the integrated electrical switch that controls ignition, accessory, and start circuits in one ready-to-install unit. Designed for 2003-2007 model year trucks, this ignition lock cylinder switch and housing replaces a worn or failed original to eliminate no-start conditions, key sticking, and intermittent power loss without reprogramming.

Key Features & Performance

• Complete assembly includes lock cylinder, ignition switch, and housing — no separate component sourcing required
• Pre-coded key tumbler matched to new keys for plug-and-play installation on most compatible models
• Heavy-duty electrical contacts resist pitting and carbon buildup that cause intermittent starting issues
• Die-cast metal housing with anti-tamper collar replicates factory security and mounting fit
• Precision-machined cylinder bore reduces key binding and ensures smooth rotation through all ignition positions
• Factory-style connector plug mates directly with existing wiring harness without splicing or adapters

Fitment & Compatibility

• 2003 Chevrolet Silverado 1500 / 2500 / 3500
• 2004 Chevrolet Silverado 1500 / 2500 / 3500
• 2005 Chevrolet Silverado 1500 / 2500 / 3500
• 2006 Chevrolet Silverado 1500 / 2500 / 3500
• 2007 Chevrolet Silverado 1500 / 2500 / 3500 (Classic Body)
• 2003 GMC Sierra 1500 / 2500 / 3500
• 2004 GMC Sierra 1500 / 2500 / 3500
• 2005 GMC Sierra 1500 / 2500 / 3500
• 2006 GMC Sierra 1500 / 2500 / 3500
• 2007 GMC Sierra 1500 / 2500 / 3500 (Classic Body)

Common Uses

• Replacing an ignition lock cylinder with a broken or stuck key that won't turn
• Fixing no-crank or intermittent start issues caused by a failed ignition switch
• Restoring full electrical accessory power when the switch contacts wear out
• Addressing security system lockouts linked to a damaged key tumbler or housing sensor
• Fleet and work truck maintenance where same-key convenience is not required

Technical Specifications

• Part Number(s): US-578L
• Ignition Positions: Off, Accessory, On, Start
• Housing Material: Die-Cast Zinc Alloy with Steel Collar
• Connector Type: Direct-Fit OEM-Style Plug
• Keys Included: 2

Frequently Asked Questions

Q: Does this ignition lock cylinder and switch assembly come with new keys? A: Yes, this assembly includes two pre-cut keys matched to the cylinder, so it is ready to install and operate immediately on compatible models.

Q: Will I need to reprogram my vehicle’s security system after installing this ignition switch housing? A: On most 2003-2007 Silverado and Sierra trucks without advanced transponder systems, no reprogramming is required. If your vehicle uses a specific anti-theft key with a chip, a relearn procedure may be needed based on your serial number.

Product appearance and specifications may vary slightly by batch. Compatibility may vary by serial number. Verify fitment before purchase.