Target Audience:
DIY enthusiasts, mechanics, Jeep owners seeking in-depth repair knowledge
Competitors 1990:
Ford Explorer, Chevrolet S-10 Blazer, Toyota 4Runner, Nissan Pathfinder
Vehicle Philosophy:
Robust construction, capable off-road performance, relatively simple mechanicals
Manual Value Proposition:
Empowers owners to perform complex repairs and maintenance, saving money and ensuring quality
Engine Options:
2.5L AMC 150 I4, 4.0L AMC 242 I6
Transmission Options:
AX4/AX4R Automatic, AX5 Manual, NV3550 Manual (late 1990 production)
Drivetrain Options:
2WD, 4WD (Command-Trac, Selec-Trac)
Body Styles:
2-door SUV, 4-door SUV
Type:
Factory Service Manual / Repair Manual
Format:
Downloadable Digital File (PDF)
Powertrain:
Engine (2.5L, 4.0L), Fuel System, Cooling System, Exhaust System, Ignition System, Engine Mechanical, Engine Electrical
Transmission Drivetrain:
Automatic Transmission (AX4/AX4R), Manual Transmission (AX5, NV3550), Transfer Case (Command-Trac, Selec-Trac), Drive Axles (Front & Rear)
Chassis Suspension Steering:
Front Suspension (Leaf Spring/Solid Axle), Rear Suspension (Leaf Spring/Solid Axle), Steering System, Brakes (Front Disc, Rear Drum), Wheels, Tires
Electrical HVAC:
Body Electrical Systems, Lighting, Instruments & Gauges, HVAC (Heating, Ventilation, Air Conditioning), Power Accessories, Fuses & Relays
Body Interior:
Body Panels, Doors, Windows, Seats, Interior Trim, Bumpers
Maintenance:
Fluid Changes (Oil, Coolant, Brake, Transmission), Filter Replacements, Lubrication, Tune-ups, Belt & Hose Inspection/Replacement
Repair Rebuild:
Engine Overhaul, Transmission Rebuild, Differential Service, Suspension Component Replacement, Brake System Overhaul, Electrical Component Diagnosis & Repair
Diagnostics Troubleshooting:
Wiring Diagrams, Diagnostic Trouble Codes (DTCs) for applicable systems, Symptom-based troubleshooting charts, Component testing procedures
Specifications Tolerances:
Torque Specifications, Clearances, Fluid Capacities, Electrical Specifications, Component Dimensions
Depth:
Comprehensive - Covers routine maintenance, troubleshooting, repair, and overhaul procedures for all major vehicle systems.
Engine 1 Displacement:
2.5 Liters (150 cu in)
Engine 1 Configuration:
Inline 4-Cylinder (I4)
Engine 1 Horsepower:
125 hp @ 4,000 rpm (approx.)
Engine 1 Torque:
200 lb-ft @ 2,000 rpm (approx.)
Engine 2 Displacement:
4.0 Liters (242 cu in)
Engine 2 Configuration:
Inline 6-Cylinder (I6)
Engine 2 Horsepower:
177 hp @ 4,750 rpm (approx.)
Engine 2 Torque:
220 lb-ft @ 3,250 rpm (approx.)
Fuel Delivery:
Electronic Fuel Injection (EFI)
Fuel Type:
Unleaded Gasoline
Compression Ratio 2.5L:
8.8:1
Compression Ratio 4.0L:
8.8:1
Manual Transmission:
AX5 5-Speed Manual
Automatic Transmission:
AX4/AX4R 4-Speed Automatic
Late Manual Transmission:
NV3550 5-Speed Manual (rare for '90)
Transfer Case Options:
New Process NV231 Command-Trac (Part-time 2WD, 4WD High, 4WD Low), New Process NV242 Selec-Trac (Full-time 4WD, Part-time 4WD High, 4WD Low)
Automatic Transmission Fluid:
Chrysler ATF+3 or equivalent (check specific manual for exact spec)
Manual Transmission Fluid:
API GL-5, SAE 75W-90 Gear Oil (check specific manual)
Engine Oil Change:
Every 3,000-5,000 miles or 6 months (depending on driving conditions and oil type)
Engine Coolant Change:
Every 30,000 miles or 2 years
Transmission Fluid Change Auto:
Every 30,000-50,000 miles
Transmission Fluid Change Manual:
Every 50,000-75,000 miles
Transfer Case Fluid Change:
Every 30,000-50,000 miles
Engine Oil 2.5L:
API SG/SH, SAE 10W-30 (or 10W-40 in cooler climates)
Engine Oil 4.0L:
API SG/SH, SAE 10W-30 (or 10W-40 in cooler climates)
Coolant:
Chrysler Type A (Green) or equivalent Ethylene Glycol based coolant
Engine 4.0L Common Issue:
Head gasket leaks, oil filter adapter housing leaks, cracked cylinder heads (less common in '90).
Suspension Common Issue:
Leaf spring sag, worn control arm bushings (due to solid axle design).
Electrical Common Issue:
Grounding issues, intermittent power to accessories.
Rust Prone Areas:
Rocker panels, rear quarter panels, floor pans, unibody frame rails.
Jeep Legacy:
Established in WWII with the Willys MB, known for ruggedness and off-road capability.
Xj Introduction:
Launched in 1984, revolutionizing the SUV market with its unibody construction.
1990 Updates:
Minor styling refinements, potential introduction of NV3550 transmission late in the model year.
Manufacturing Plant:
Toledo, Ohio, USA
Production Span Xj:
1984-2001
🏆 Professional Vehicle Manual Information
Comprehensive technical documentation for maintenance, repair, and operation