The 2003 Buick Regal represents a continuation of Buick's legacy in producing comfortable and well-equipped American sedans. Positioned as a sporty yet upscale mid-size sedan, this model is built on the robust GM W-body platform. It was offered with a 3.8L V6 engine, available in naturally aspirated (L36) and supercharged (L67) variants, providing a blend of performance and refinement. With standard features like anti-lock brakes and available traction control, along with a strong safety rating, the Regal was designed to offer a reliable and enjoyable driving experience for owners. This comprehensive factory service manual provides in-depth, vehicle-specific repair and maintenance information for all 2003 Buick Regal models. Covering a vast array of systems from engine diagnostics and mechanical repairs to electrical systems and bodywork, this manual offers factory-level detail. It includes complete step-by-step instructions, detailed diagrams, wiring schematics, and troubleshooting guides. This resource is invaluable for Buick Regal owners, DIY mechanics, and professional technicians seeking to maintain, diagnose, and repair their vehicles efficiently and accurately, ensuring optimal performance and longevity. 🏷️ Basic Information Identification Make: Buick Model: Regal Year: 2003 Codes Platform Code: W-body 👋 Introduction Market Position Target Audience: Buick Regal owners, DIY mechanics, professional repair shops Competitive Analysis Value Proposition: Provides factory-level diagnostic and repair information, saving time and money compared to relying solely on mechanics. Key Features Ease Of Use: Single, easy-to-use PDF manual, no flipping through multiple books. Portability: Printable pages allow for easy transport to the garage or workshop. Durability: Digital format prevents greasy pages or torn paper manuals. 📋 Manual Details Coverage Areas Covered Models: All Buick Regal models Repair Scope: A-Z, vehicle-specific Page Count Estimated Page Count: Extensive (typical for full factory service manuals, often 1500+ pages) Manual Type Type: Factory Service Manual / Repair Manual Language Language: English Format Format: PDF Download 📖 Manual Coverage Systems Covered Engine Maintenance: Included Engine Diagnostics: Included Control Systems: Included Mechanical Repairs: Included Fuel System Service: Included Emission Control Systems: Included Intake Exhaust Cooling: Included Lubrication System: Included Ignition Starting Charging: Included Automatic Transmission Clutch: Included Manual Transmission: Included Transfer Propeller Shaft: Included Drive Shaft: Included Differential: Included Axle Suspension: Included Tire Wheel Assembly: Included Brake Control Systems: Included Brake Systems: Included Parking Brake System: Included Steering Column: Included Power Steering System: Included Air Conditioning System: Included Supplemental Restraint System Srs: Included Seat Belt Systems: Included Engine Immobilizer System: Included Cruise Control System: Included Wiper Washer System: Included Door Lock Systems: Included Meter Audio Visual Systems: Included Horn System: Included Windshield Glass Mirror Systems: Included Instrument Panel Systems: Included Seat Systems: Included Engine Hood Door Systems: Included Exterior Interior Trim: Included Electrical Systems General: Included Multiplex Can Communication: Included Procedures Included Maintenance Procedures: Complete step-by-step instructions Diagnostic Procedures: Included Repair Procedures: Complete step-by-step instructions for all repairs Troubleshooting Guides: Included Technical Depth Depth: Factory-level detail, suitable for professional technicians and advanced DIYers Wiring Information: Wiring schematics included Illustrations Diagrams: Detailed diagrams and illustrations included 📊 Manual Specifications File Format Compatibility: Windows (Vista 32/64, XP, ME, 98, NT, 2000) and Mac Reader Requirement: Adobe PDF Reader Unzip Requirement: Winzip (or equivalent) Print Quality Printability: All pages printable Image Scaling: Ability to blow up images for enlarged printing Binding Type Binding Type: N/A (Digital PDF) Paper Type Paper Type: N/A (Digital PDF) ⚙️ Engine Specifications Primary Engine Engine Options 2003: 3.8L V6 (L36 naturally aspirated, L67 supercharged) Performance L36 Horsepower: Approx. 205 hp @ 5200 rpm L36 Torque: Approx. 230 lb-ft @ 4000 rpm L67 Horsepower: Approx. 240 hp @ 5200 rpm L67 Torque: Approx. 280 lb-ft @ 3600 rpm Fuel System Fuel Delivery: Sequential Fuel Injection (SFI) 🔧 Transmission Standard Standard Transmission: 4-speed automatic (4T65-E) Optional Optional Transmission: 4-speed automatic with manual shift mode (4T65-E HD for supercharged models) Features Transmission Fluid: Dexron III (or Dexron VI as a replacement) 📐 Dimensions Exterior Wheelbase: Approx. 110.5 inches Length: Approx. 197.3 inches Width: Approx. 71.4 inches Height: Approx. 55.7 inches Weights Curb Weight: Varies by model and options, typically 3400-3700 lbs 🛡️ Safety Features Ratings NHTSA Frontal Driver Rating: 5-star (for most configurations) NHTSA Frontal Passenger Rating: 5-star (for most configurations) Active Features ABS: Standard Traction Control: Optional or standard depending on trim/engine (often called Traction Control System - TCS) Passive Features Airbags: Driver and front passenger airbags; optional side airbags 💡 Technology Features Infotainment Audio System: Factory AM/FM/CD player, optional premium sound systems, steering wheel audio controls. Driver Assistance Key Features: Cruise control, optional anti-lock brakes (ABS). Connectivity Cellular Connectivity: No built-in cellular connectivity typical for this era. 🔧 Maintenance Service Intervals Oil Change Interval: Typically 3,000-5,000 miles or 3-6 months, depending on driving conditions and oil type used. Transmission Fluid Change Interval: Refer to manual, typically 50,000-100,000 miles for severe service. Fluid Specifications Engine Oil Specification: API Certified SAE 5W-30 (viscosity may vary slightly based on...