Engine Mechanical:
Complete engine overhaul, disassembly, assembly, inspection, timing procedures
Engine Fuel System:
Fuel injection system, fuel pump, injectors, pressure regulator, diagnosis
Engine Cooling System:
Radiator, water pump, thermostat, hoses, fan, coolant specifications
Engine Ignition System:
Distributor, ignition coil, spark plugs, wires, timing, diagnosis
Engine Lubrication System:
Oil pump, oil filter, oil pressure, oil specifications
Emission Control System:
Catalytic converter, EGR system, PCV system, diagnosis
Transmission Automatic:
Disassembly, assembly, diagnosis, fluid specifications, torque converter
Transmission Manual:
Disassembly, assembly, clutch, gearbox, fluid specifications
Drivetrain 4Wd System:
Transfer case operation, maintenance, diagnosis, front axle, rear axle
Steering System:
Power steering pump, rack and pinion, linkages, fluid specifications
Suspension System:
Front suspension (leaf springs, shocks), rear suspension (leaf springs, shocks), alignment
Brake System:
Front disc brakes, rear drum brakes, parking brake, hydraulic system, ABS (if equipped)
Electrical System:
Wiring diagrams, battery, alternator, starter, lighting, fuses, relays
HVAC System:
Air conditioning, heating, ventilation, blower motor, controls
Body And Chassis:
Body panels, doors, windows, interior trim, structural components
Routine Maintenance:
Oil changes, filter replacements, fluid checks, tire rotations
Troubleshooting Guides:
Diagnostic flowcharts for common drivability and system issues
Component Replacement:
Step-by-step guides for replacing major and minor components
Diagnostic Procedures:
On-board diagnostics (OBD-I) interpretation, sensor testing
Special Tools:
Identification and usage of specialized tools required for specific repairs
Depth:
Comprehensive rebuild procedures, advanced diagnostics, detailed schematics
Engine Code 1:
4.0L Inline 6-Cylinder (242 cu in)
Engine Displacement 1:
3960 cc
Engine Bore Stroke 1:
98.5 mm x 86.6 mm
Engine Compression Ratio 1:
8.8:1
Engine Horsepower 1:
180 hp @ 4750 rpm (approx.)
Engine Torque 1:
220 lb-ft @ 3250 rpm (approx.)
Fuel Induction 1:
Multi-point Fuel Injection (MPI)
Recommended Fuel 1:
87 Octane Unleaded Gasoline
Engine Code 2:
2.5L Inline 4-Cylinder (150 cu in) 'Tech'
Engine Displacement 2:
2474 cc
Engine Horsepower 2:
125 hp @ 4800 rpm (approx.)
Engine Torque 2:
147 lb-ft @ 2500 rpm (approx.)
Oil Change Interval:
Every 3,000 miles or 3 months (under severe conditions), 5,000 miles or 6 months (under normal conditions)
Air Filter Replacement:
Every 15,000 miles or 12 months
Spark Plug Replacement:
Every 30,000 miles (check manual for specific type)
Transmission Fluid Change:
Every 30,000 miles or 24 months
Coolant Flush:
Every 30,000 miles or 24 months
Engine Oil Type 1:
API SG, SAE 10W-30 (preferred for 4.0L), SAE 5W-30 in very cold climates
Engine Oil Capacity 1:
5 US quarts (4.7 liters) with filter change (4.0L)
Coolant Type:
Ethylene Glycol (Green) - 50/50 mix with distilled water
Common Problem 1:
Rear main seal leaks (especially on higher mileage 4.0L engines)
Common Problem 2:
Head gasket issues on early 4.0L engines (though less common by '93)
Common Problem 3:
Transfer case chain stretch/slipping
Common Problem 4:
Front axle universal joint (U-joint) wear, especially with 4WD usage
Common Problem 5:
Cracked exhaust manifolds (especially on the 4.0L)
