🏷️ Basic Information

Make:

Buick

Model:

Regal

Year:

2003

Generation:

Fifth Generation (G-Body, W-Body Facelift)

Platform:

W-Body (GMT122)

👋 Introduction

Positioning:

The 2003 Buick Regal was positioned as a mid-size sedan offering a comfortable and refined driving experience, often appealing to a mature demographic seeking value and reliability. It competed with models like the Toyota Camry, Honda Accord, and Ford Taurus.

Comparison Points:

The Regal's key differentiators included its powerful V6 engine options (especially the supercharged Grand Prix GTP-derived L67), comfortable ride quality, and a more traditional American luxury feel compared to its Japanese rivals. Interior space and trunk capacity were competitive within its segment.

Highlighted Features:

Optional Supercharged 3.8L V6 engine, refined interior appointments, comfortable ride, available Driver Information Center, premium sound systems.

Manual Advantage:

Provides factory-derived information, ensuring accuracy and completeness, unlike aftermarket condensed guides.

📋 Manual Details

Primary Coverage:

Service, Repair, Maintenance, Diagnostics

Estimated Page Count:

Varies by specific content, often 1000+ pages for comprehensive factory data

Type:

Factory-Derived Service & Repair Manual Software

Language:

English

Format:

PDF Download

📖 Manual Coverage

Engine:

3.8L V6 (L36, L67 Supercharged), 3.9L V6 (L32 OHV)

Drivetrain:

Front-Wheel Drive (FWD), Automatic Transmissions (4T65-E, 4T65-E HD)

Brakes:

Front Disc (Vented), Rear Disc, ABS System

Suspension:

Front MacPherson Strut, Rear Independent Suspension (Chapman Strut/Trailing Arm)

Steering:

Rack and Pinion, Power Steering

Electrical:

Wiring Diagrams, Body Control Module (BCM), Powertrain Control Module (PCM), Lighting, Instruments, Accessories

HVAC:

Heating, Ventilation, Air Conditioning (Manual and Automatic Climate Control)

Body:

Exterior Panels, Interior Trim, Doors, Windows, Seats, Safety Restraints (Airbags)

Maintenance:

Oil Changes, Filter Replacements, Fluid Checks and Top-offs, Spark Plug Replacement, Belt Inspection and Replacement

Repair:

Engine Component Replacement, Transmission Servicing, Brake System Overhaul, Suspension Component Replacement, Steering System Repair, Electrical Component Diagnosis and Replacement, HVAC System Servicing

Diagnostics:

Troubleshooting Guides, Diagnostic Trouble Codes (DTCs), Explanations of System Operation

Technical Specifications:

Torque Specifications, Clearances, Fluid Capacities, Electrical Specifications

Body And Trim:

Interior trim removal and installation, exterior panel alignment and replacement, door and window regulator repair, bumper cover servicing.

Exhaust System:

Catalytic converter replacement, muffler and pipe replacement, exhaust hanger repair.

Fuel System:

Fuel pump replacement, fuel filter replacement, fuel injector servicing, evaporative emissions (EVAP) system troubleshooting.

Cooling System:

Radiator replacement, water pump replacement, thermostat replacement, coolant hose replacement, heater core servicing.

Depth:

Comprehensive; covers everything from basic maintenance to advanced diagnostics and component-level repair.

Diagnostic Tools:

Guidance on using OBD-II scanners, understanding live data streams, and interpreting diagnostic trouble codes (DTCs).

📊 Manual Specifications

File Type:

PDF

Searchability:

Searchable text allows for quick location of specific topics.

Quality:

High-resolution scans of factory documentation, ensuring clarity of diagrams and text.

Binding:

N/A (Digital Download)

Paper:

N/A (Digital Download)

⚙️ Engine Specifications

Engine Code 1:

L36 (3.8L V6)

Displacement 1:

3.8 Liters (231 cubic inches)

Configuration 1:

Naturally Aspirated, Overhead Valve (OHV)

Horsepower 1:

200 hp @ 5200 rpm

Torque 1:

225 lb-ft @ 4000 rpm

Engine Code 2:

L67 (3.8L V6 Supercharged)

Displacement 2:

3.8 Liters (231 cubic inches)

Configuration 2:

Supercharged, Overhead Valve (OHV)

Horsepower 2:

240 hp @ 5200 rpm

Torque 2:

280 lb-ft @ 3600 rpm

Engine Code 3:

L32 (3.9L V6 OHV)

Displacement 3:

3.9 Liters (237 cubic inches)

Configuration 3:

Overhead Valve (OHV)

Horsepower 3:

175 hp @ 4800 rpm

Torque 3:

230 lb-ft @ 3200 rpm

Fuel Delivery:

Multi-Port Fuel Injection (MPFI)

Fuel Type:

Unleaded Gasoline (87 Octane Recommended)

🔧 Transmission

Type Standard:

4-Speed Automatic (4T65-E)

Type Optional:

4-Speed Automatic Heavy Duty (4T65-E HD - typically with supercharged engine)

Transmission Features:

Driver-Shift Control (Selectable Gear Positions), Tow/Haul Mode (if equipped), Electronic Controls.

📐 Dimensions

Length:

Approx. 196.3 inches

Width:

Approx. 71.4 inches

Height:

Approx. 56.7 inches

Wheelbase:

Approx. 109.0 inches

Curb Weight Min:

Approx. 3,400 lbs (Varies by trim and engine)

Gross Vehicle Weight Rating:

Approx. 4,500 lbs (Varies by configuration)

🛡️ Safety Features

NHTSA Front Impact Driver:

Good (Top Safety Pick)

NHTSA Front Impact Passenger:

Good (Top Safety Pick)

NHTSA Side Impact Driver:

Acceptable

NHTSA Side Impact Rear Passenger:

Acceptable

IIHS Front Offset:

Good (Acceptable/Good depending on specific test results year)

ABS:

Standard (Anti-lock Braking System)

Traction Control:

Optional (TCS - Traction Control System)

Airbags Front:

Standard Dual Frontal Airbags

Airbags Side:

Optional Front Side Impact Airbags

Seatbelts:

Three-Point Seatbelts (All Seating Positions), Pretensioners (Front)

💡 Technology Features

Audio System:

AM/FM Stereo with CD Player, Cassette Player (optional), Premium Sound System Options (e.g., Monsoon).

Climate Control:

Manual HVAC or optional Automatic Climate Control.

Cruise Control:

Standard

Keyless Entry:

Optional

Onstar:

Available with subscription.

🔧 Maintenance

Oil Change Interval:

Every 3,000-5,000 miles or 3-6 months, depending on driving conditions (consult manual for specific recommendations based on oil type).

Tire Rotation Interval:

Every 5,000-7,500 miles

Transmission Fluid Interval:

Inspect every 30,000 miles, change as needed (typically around 50,000-100,000 miles depending on severe use).

Engine Oil Spec:

SAE 5W-30 (API Certified)

Engine Oil Capacity:

4.5 US quarts (with filter)

Coolant Spec:

Dex-Cool (GM 1825M) Extended Life Antifreeze/Coolant (50/50 mixture with distilled water)

Transmission Fluid Type:

Dexron III (or equivalent)

Brake Fluid Type:

DOT 3

Common Problems:

Intake manifold gasket leaks, power steering pump failure, fuel pump issues, PCM failures, coolant leaks (especially around the Northstar V8 if equipped in other W-body models, though less common in Regal), occasional transmission shifting issues.

📚 Vehicle History

Buick Legacy:

Buick has a long-standing reputation for producing comfortable, well-appointed, and durable vehicles, often positioned as a premium American marque.

Regal Lineage:

The Regal nameplate has been used by Buick since 1973, evolving through various platforms and styles, becoming a staple in Buick's lineup known for comfort and performance variants.

Manufacturing Location:

Oshawa, Ontario, Canada; Lake Orion, Michigan, USA (GM Assembly Plants)

🏆 Awards & Recognition

Safety Awards:

Received 'Good' ratings in front-impact crash tests from the IIHS and NHTSA.