Vehicle Segment:
Compact SUV / Off-Road Vehicle
Brand Positioning:
Iconic American off-road capability, ruggedness, and utilitarian design
Key Competitors 1998:
Toyota Land Cruiser (lower trims), Suzuki Vitara, Mitsubishi Montero Sport
Off Road Capability:
Solid front and rear axles, robust four-wheel-drive system (Command-Trac NV231 or optional Selec-Trac NV242), high ground clearance, short wheelbase
Design:
Classic Jeep grille, round headlights, removable doors and top (full-steel or soft top options)
Powertrain Options:
Durable inline-6 and inline-4 engine options, available manual and automatic transmissions
Systems Covered:
Engine, Transmission, Drivetrain, Suspension, Steering, Brakes, Electrical System, HVAC, Body & Chassis, Emissions Control, Troubleshooting, Diagnostics, Routine Maintenance, Specifications, Wiring Diagrams
Estimated Page Count:
1500+
Type:
Factory Service Manual (FSM) / Repair Manual
Format:
Digital Download (PDF)
Engine Mechanical:
Detailed overhaul procedures, component testing, timing, lubrication, cooling system, fuel system, exhaust system
Engine Performance:
Ignition system diagnosis and repair, fuel injection operation and troubleshooting, emissions control systems
Transmission Manual:
Service and repair of AX-5 and NV3550 manual transmissions, clutch system, shift linkage
Transmission Automatic:
Service and repair of 30RH and 42RE automatic transmissions, torque converter, valve body, shift control
Drivetrain:
Front and rear axle service (Dana 30, Dana 35), differential overhaul, transfer case (NP231) service, driveshaft maintenance
Suspension:
Front and rear suspension component replacement (coil springs, shocks, control arms), alignment specifications
Steering:
Power steering system diagnosis and repair, steering gear, tie rod ends, steering column
Brakes:
Front disc brake service, rear drum brake service (or optional rear discs), ABS system diagnosis (if equipped), brake hydraulic system
Electrical System:
Battery, charging system (alternator), starting system (starter), lighting system, accessory circuits, fuses, relays
HVAC:
Air conditioning system service, heater core replacement, blower motor, climate controls
Body Chassis:
Body panel repair, door mechanisms, interior trim, convertible top service, frame inspection and repair
Emissions Control:
Catalytic converter, oxygen sensors, EGR system, evaporative emission control system
Maintenance:
Oil change intervals, filter replacement, fluid checks and changes, spark plug replacement, belt inspection and replacement, tire rotation
Troubleshooting:
Systematic diagnostic procedures for common and uncommon issues, symptom-based troubleshooting guides
Repair:
Step-by-step repair instructions for all major vehicle components and systems
Diagnostics:
Diagnostic Trouble Codes (DTCs), on-board diagnostics (OBD-II) information, electrical troubleshooting using schematics
Specifications:
Torque specifications, clearances, fluid capacities, electrical data, alignment angles, tire pressures
Depth:
Comprehensive coverage from basic maintenance to full engine and transmission rebuilds, including advanced diagnostic techniques and wiring diagrams
Transmission Standard Short Wheelbase:
5-speed Manual (AX-5)
Transmission Standard Long Wheelbase:
6-speed Manual (NV3550) - Introduced mid-year for some models
Transmission Optional:
4-speed Automatic (30RH or 42RE)
Transfer Case Standard:
New Process NP231 Command-Trac (Part-Time 4WD)
Transfer Case Optional:
New Process NP242 Selec-Trac (Full-Time 4WD option)
Oil Change Interval:
Every 3,000 miles (4,800 km) or 3 months (whichever comes first) under normal conditions; 7,500 miles (12,000 km) or 6 months under severe conditions (refer to manual for specifics)
Engine Oil Filter Replacement:
With every oil change
Spark Plug Replacement 4.0L:
Approx. 100,000 miles (160,000 km)
Transmission Fluid Change Manual:
Check every 30,000 miles (48,000 km), change as needed
Transmission Fluid Change Automatic:
Every 30,000 miles (48,000 km) or 24 months
Engine Oil Spec:
API SG or higher, SAE 10W-30 (check owner's manual for climate-specific recommendations)
Engine Coolant Spec:
Chrysler/Mopar OAT (Organic Additive Technology) or HOAT, 50/50 mix with distilled water
Transfer Case Fluid Spec Np231:
Mopar ATF+4 (or equivalent Dexron III/Mercon)
Automatic Transmission Fluid Spec:
Mopar ATF+4 (or equivalent Dexron III/Mercon)
Common Problems 1998 Wrangler:
Cracked exhaust manifolds (4.0L engine), radiator leaks, heater core failures, rear main seal leaks (4.0L), door hinge rust, sway bar link wear, "death wobble" (requires careful diagnosis of suspension and steering components).
