Engine Mechanical:
Detailed overhaul and repair procedures for all YJ engine variants.
Fuel System:
Diagnosis and repair of fuel injection, carburetion (early models), fuel pumps, and lines.
Cooling System:
Radiator, water pump, thermostat, hoses, and fan system repair.
Exhaust System:
Catalytic converter, muffler, exhaust manifold, and pipe repair.
Transmission Manual:
Overhaul and repair of AX-4, AX-5, and AX-15 manual transmissions.
Transmission Automatic:
Overhaul and repair of the TF-999 and 30RH automatic transmissions.
Transfer Case:
Service and repair for NP228, NP229, and NP231 transfer cases.
Drivetrain Axles:
Dana 30 front and Dana 35C rear axle service, including differential and hub maintenance.
Suspension Front:
Leaf spring, shock absorber, and steering linkage repair.
Suspension Rear:
Leaf spring, shock absorber, and U-bolt service.
Steering System:
Power steering pump, steering gear, and tie rod end repair.
Brake System:
Front disc and rear drum brake service, including master cylinder, calipers, wheel cylinders, and parking brake.
Electrical System Charging:
Alternator, voltage regulator, and battery system diagnostics.
Electrical System Ignition:
Spark plugs, wires, distributor, ignition coil, and module service.
Electrical System Lighting:
Headlights, taillights, turn signals, and interior lighting diagnostics and repair.
Electrical System Accessories:
Wipers, horn, power windows, locks, and radio system troubleshooting.
Climate Control:
HVAC system repair, including blower motor, heater core, and A/C system servicing.
Body Exterior:
Panel alignment, door hinge and lock repair, convertible top service (if applicable).
Body Interior:
Seat removal, dashboard disassembly, and trim panel replacement.
Routine Maintenance:
Oil changes, filter replacements, fluid checks, tire rotation, and belt inspection.
Engine Diagnostics:
Troubleshooting engine performance issues, misfires, and starting problems.
Transmission Repair:
Step-by-step guides for transmission disassembly, inspection, and reassembly.
Brake Service:
Brake pad/shoe replacement, rotor/drum resurfacing, brake fluid bleeding, and hydraulic system repair.
Electrical Troubleshooting:
Wiring diagrams, component testing, and diagnostic procedures for electrical faults.
Suspension Alignment:
Specifications and procedures for suspension component replacement and alignment.
Engine Rebuild:
Complete instructions for engine disassembly, component measurement, and reassembly.
Body Repair:
Procedures for dent removal, panel replacement, and rust repair.
Diagnostic Codes:
Explanation and interpretation of diagnostic trouble codes (DTCs) where applicable.
Depth:
Factory-level detail, suitable for professional technicians and experienced DIY mechanics.
Engine Options:
2.5L AMC I4 (e.g., "Tech-4"), 4.0L AMC I6 (legendary for torque and durability).
4.0L I6 Power:
Approximately 182-190 horsepower, 220-235 lb-ft of torque (depending on year and specific tune).
2.5L I4 Power:
Approximately 105-130 horsepower, 130-155 lb-ft of torque (depending on year and specific tune).
0-60 Mph Times:
Highly variable based on engine, transmission, and gearing, generally in the 9-12 second range for the 4.0L.
Injection Type:
Multi-port fuel injection (MPI) for most models, some earlier models may have featured throttle body injection (TBI) or even carburetion for the 4-cylinder.
Oil Change Interval:
Typically every 3,000 miles or 3 months (consult manual for specific engine/oil type).
Transmission Fluid Change:
Every 30,000-50,000 miles, depending on usage (manual specifies exact intervals).
Coolant Flush:
Every 24,000-30,000 miles or 2-3 years.
Engine Oil:
API SJ or higher, viscosity typically 10W-30 for the 4.0L I6, 5W-30 or 10W-30 for the 2.5L I4 (refer to manual for precise specifications).
Transmission Fluid Auto:
Chrysler ATF+4 or equivalent (earlier models may specify ATF+3 or Dexron III).
Transmission Fluid Manual:
GL-4 or GL-5 gear oil, typically 75W-90 or 80W-90 for manual transmissions.
Transfer Case Fluid:
ATF+4 or equivalent for NP231, specific gear oil for others (refer to manual).
Coolant:
Ethylene glycol based coolant, typically a 50/50 mix with distilled water.
Common Problems:
Common issues include rust (especially rocker panels and floor pans), cracked exhaust manifolds on the 4.0L, worn leaf spring bushings, aging electrical components, and radiator leaks.
