🏷️ Basic Information

Make:

Jeep

Model:

Wrangler

Year:

2003

Internal Model Code:

TJ

👋 Introduction

Positioning:

The 2003 Jeep Wrangler (TJ) is a compact, convertible SUV known for its off-road capabilities, open-air driving experience, and utilitarian design.

Competitors:

Competes with vehicles like the Toyota 4Runner, Land Rover Defender (in global markets), and other off-road oriented SUVs, though its unique body-on-frame construction and solid axles set it apart.

Defining Characteristics:

Iconic Wrangler styling, removable doors and top, solid front and rear axles with coil springs, selectable 4WD system (Command-Trac or optional NV241OR Rock-Trac), and robust off-road performance.

📋 Manual Details

Manual Type:

Service and Repair Manual

Language:

English

Format:

Printed Book

Coverage Scope:

Covers all models and all repairs A-Z

Oem Quality:

This manual is the exact same information used by dealership technicians, ensuring OEM-level accuracy and completeness.

Estimated Page Count:

Approximately 1000-1500 pages (typical for comprehensive factory service manuals)

📖 Manual Coverage

Engine:

Detailed diagnostics, repair, and overhaul for 4.0L I6 and 2.4L I4 engines, including fuel, ignition, emissions, cooling, lubrication, and performance tuning.

Transmission:

Repair and overhaul for NV3550 5-speed manual transmission and 42RLE 4-speed automatic transmission, including torque converter, clutch, and driveline components.

Brakes:

Front and rear disc brake systems, ABS diagnostics and repair, parking brake, hydraulic system troubleshooting.

Electrical:

Complete wiring diagrams, diagnostic procedures for body control module (BCM), Powertrain Control Module (PCM), lighting, power accessories, audio systems, and instrument cluster.

Suspension:

Front and rear suspension component inspection, replacement, and alignment specifications for solid axles (Dana 30 front, Dana 35 rear).

Steering:

Power steering system diagnosis and repair, steering column, steering gear (Steering box), and linkage.

Body:

Body panel repair, door mechanisms, latches, hinges, convertible top service, interior trim removal and installation, and HVAC system repair.

Driveline And Axles:

Comprehensive coverage of front and rear axles (Dana 30, Dana 35, Dana 44 for Rubicon), axle ratios, differential service, CV joints, U-joints, and driveshafts.

Cooling System:

Radiator, water pump, thermostat, hoses, fan clutch, and coolant recovery system diagnostics and replacement.

Exhaust System:

Exhaust manifold, catalytic converter, muffler, pipes, and oxygen sensor replacement and troubleshooting.

Maintenance:

Scheduled maintenance intervals, oil changes, filter replacements, lubrication points, belt inspections, and fluid level checks.

Troubleshooting:

Systematic diagnostic flowcharts and symptom-based troubleshooting guides for common and complex issues.

Repair:

Step-by-step instructions for component removal, installation, and adjustment for all major vehicle systems.

Diagnostics:

Detailed diagnostic procedures for mechanical, electrical, and electronic systems, including use of diagnostic scan tools and interpretation of fault codes.

Torque Specifications:

Includes detailed torque specifications for all critical fasteners, including engine components, suspension, and driveline.

Depth:

Vehicle-specific, technician-level detail, covering everything from basic fluid changes to complete engine and transmission overhauls.

Diagnostic Tools:

Covers procedures for using OBD-II scanners, multimeter testing, and specific diagnostic equipment for various systems.

📊 Manual Specifications

Digital Availability:

Likely available as a printed manual, with potential for unofficial PDF scans. Official digital versions are typically subscription-based.

Paper Quality:

Typically printed on durable, high-quality paper suitable for workshop environments.

Binding:

Spiral-bound or perfect-bound for ease of use on a workbench.

All Models Trims:

Yes, covers Sport, Sahara, Rubicon, and other trim variants of the 2003 Jeep Wrangler.

⚙️ Engine Specifications

Engine 1 Name:

4.0L I6 (Power Tech)

Engine 1 Displacement:

3952 cc (241 cu in)

Engine 1 Configuration:

Inline 6-cylinder, Overhead Valve (OHV)

Engine 1 Horsepower:

190 hp @ 4600 rpm

Engine 1 Torque:

235 lb-ft @ 3200 rpm

Engine 1 Part Number Block Typical:

Consult specific service data for exact part numbers, but typically identified by casting marks like '237' for the 4.0L block.

Engine 2 Name:

2.4L I4 (EDZ PowerTech)

Engine 2 Displacement:

2429 cc (148 cu in)

Engine 2 Configuration:

Inline 4-cylinder, Single Overhead Camshaft (SOHC)

Engine 2 Horsepower:

147 hp @ 5200 rpm

Engine 2 Torque:

177 lb-ft @ 4000 rpm

Fuel Delivery:

Electronic Fuel Injection (MPI)

Recommended Fuel:

87 Octane Unleaded gasoline

🔧 Transmission

Transmission 1 Type:

NV3550 5-Speed Manual

Transmission 2 Type:

42RLE 4-Speed Automatic

Transfer Case:

NV131 (Command-Trac) part-time, 2-speed transfer case (standard). NV241OR (Rock-Trac) part-time, 2-speed transfer case with 4.0:1 low range (optional on Rubicon models).

📐 Dimensions

Wheelbase 2 Door:

93.4 inches (2372 mm)

Length 2 Door:

151.4 inches (3845 mm)

Width 2 Door:

66.5 inches (1689 mm)

Height 2 Door With Hardtop:

71.3 inches (1811 mm)

Wheelbase 4 Door Unavailable For 2003:

N/A (The 4-door Wrangler Unlimited (LJ) debuted in 2004 model year).

Curb Weight 2 Door 4.0L:

Approximately 3,100 - 3,400 lbs (1406 - 1542 kg)

Gross Vehicle Weight Rating Gvwr 2 Door:

Approximately 4,500 lbs (2041 kg)

🛡️ Safety Features

NHTSA Rollover Resistance:

4 out of 5 stars (typical for TJ models)

Braking System:

Front disc, rear disc brakes. Optional Anti-lock Braking System (ABS) on rear wheels.

Airbags:

Driver and passenger front airbags.

Seat Belts:

Three-point front seat belts, two-point rear seat belts.

💡 Technology Features

Audio System Options:

Base AM/FM radio, optional CD player, optional Infinity premium audio system with subwoofer.

ABS:

Optional Anti-lock Braking System (ABS) available on rear wheels.

Power Windows Locks:

Optional power windows and power door locks were available on higher trim levels.

🔧 Maintenance

Oil Change Interval 4.0L:

Every 5,000 miles (8,000 km) or 6 months, whichever comes first.

Engine Oil Filter Replacement:

Replace with oil change.

Air Filter Replacement:

Inspect every 15,000 miles (24,000 km), replace as needed. Replace every 30,000 miles (48,000 km).

Transmission Fluid Change Manual:

Check fluid level regularly, change fluid approximately every 50,000 miles (80,000 km) or as recommended by manual.

Transmission Fluid Change Automatic:

Check fluid level regularly, change fluid and filter approximately every 30,000 miles (48,000 km) under normal driving conditions, more frequently under severe use.

Engine Oil Type:

SAE 10W-30 API Service SG or SH (consult manual for exact spec for 4.0L I6)

Engine Coolant Type:

Mopar Antifreeze/Coolant (HOAT) or equivalent, 50/50 mix with distilled water.

Transmission Fluid Manual:

MS-9224 or equivalent synthetic manual transmission fluid (e.g., Castrol Syntrans, Red Line MTL)

Transmission Fluid Automatic:

Chrysler ATF+4 (MS-9602)

Transfer Case Fluid:

NV231/NV131: ATF+4 (MS-9602). NV241OR: NV241OR spec fluid (consult manual for exact type).

Axle Fluid Front Rear:

SAE 75W-90 GL-5 synthetic gear lubricant. Add friction modifier for limited-slip differentials (if equipped).

Power Steering Fluid:

Chrysler Power Steering Fluid (MS-5901) or equivalent.

Common Problems:

Oil leaks (valve cover gasket, oil pan gasket), radiator leaks, clutch wear (manual transmission), PCM failures, wiper motor issues, death wobble (front suspension/steering linkage components). Rear axle seal leaks.

Frame Rust:

The frame is susceptible to rust, especially in areas with road salt. Regular inspection and rust prevention are crucial.

📚 Vehicle History

Jeep Legacy:

Jeep has a storied history dating back to World War II with the Willys MB, establishing a reputation for ruggedness and off-road capability.

Tj Generation:

The TJ Wrangler, introduced for the 1997 model year, replaced the YJ and marked a significant departure with the return of coil springs and the elimination of the leaf-sprung 'leafy' rear suspension. This generation is celebrated for its blend of classic Jeep characteristics with improved on-road manners and modern features.

Manufacturing Location:

Toledo, Ohio, USA

Model Years Tj:

1997-2006

🏆 Awards & Recognition

Off Road Awards:

The Jeep Wrangler platform, including the TJ, consistently receives accolades from off-road publications and enthusiasts for its trail performance and ruggedness.