🏷️ Basic Information

Make:

Jeep

Model:

Cherokee

Model Code:

XJ

Year:

1991

👋 Introduction

Positioning:

The 1991 Jeep Cherokee XJ represented a pinnacle of compact SUV utility and capability, appealing to off-road enthusiasts and those seeking a robust, reliable vehicle for diverse conditions. This manual serves as the definitive guide for maintaining and repairing this iconic model.

Competitors:

Competed against vehicles like the Ford Bronco II, Chevrolet S-10 Blazer, and Nissan Pathfinder, but often outsold them due to its superior unibody construction, renowned 4.0L inline-six engine, and legendary off-road prowess.

Vehicle Features:

Unibody construction (early SUV with this), compact dimensions, strong off-road capability (Command-Trac and Selec-Trac 4x4 systems), comfortable ride for its class, durable 4.0L I6 engine.

📋 Manual Details

Vehicle Coverage:

All 1991 Jeep Cherokee XJ models

Page Count:

Approximately 1000+ pages (estimated for comprehensive service manuals of this era)

Manual Type:

Factory Service Repair Manual

Language:

English

Format:

Print (OEM or high-quality aftermarket reproduction)

📖 Manual Coverage

Powertrain:

Engine mechanical (4.0L I6, 2.5L I4), cooling system, fuel system, exhaust system, ignition system, engine electrical, automatic and manual transmissions (AW4, AX-4, AX-5), transfer case (NP231, NP242)

Chassis:

Front and rear suspension (leaf spring, coil spring), steering system, brake system (front discs, rear drums), drivetrain (4WD, RWD), wheels and tires

Body And Electrical:

Body and frame, exterior trim, interior trim, HVAC system, lighting, instrumentation, power accessories (windows, locks, mirrors), wiring diagrams, fuses and relays, diagnostic trouble codes (DTCs)

Maintenance:

Routine maintenance schedules, fluid changes (oil, coolant, transmission, brake, transfer case, differential), filter replacements, lubrication points, tire rotation and pressure checks

Diagnostics:

Troubleshooting guides, symptom analysis, diagnostic flowcharts, electrical system diagnostics, emissions control system diagnostics

Repair And Rebuild:

Engine overhaul, cylinder head service, fuel injector testing, transmission overhaul, clutch replacement, brake caliper and rotor replacement, suspension component replacement, steering gearbox overhaul, body panel repair

Depth:

Comprehensive, covering everything from basic fluid checks and adjustments to complete engine and transmission rebuilds, including detailed diagnostic procedures and torque specifications for all components.

📊 Manual Specifications

File Format:

Printed, bound book

Print Quality:

High-resolution print, clear diagrams and illustrations

Binding Type:

Durable perfect binding or spiral binding for lay-flat usability in a shop environment

Paper Type:

Heavy-duty, gloss-coated paper to resist grease and wear in a workshop setting

⚙️ Engine Specifications

Engine Options:

2.5L AMC 150 I4 (MPFI), 4.0L AMC 242 I6 (MPFI)

4.0L Engine Specs:

Displacement: 3960cc (242 cu in), Bore x Stroke: 3.875 x 3.414 in (98.4 x 86.7 mm), Compression Ratio: 8.8:1, Horsepower: 177 hp @ 4750 rpm, Torque: 220 lb-ft @ 3250 rpm

2.5L Engine Specs:

Displacement: 2467cc (150 cu in), Bore x Stroke: 3.875 x 3.250 in (98.4 x 82.5 mm), Compression Ratio: 8.8:1, Horsepower: 125 hp @ 4600 rpm, Torque: 150 lb-ft @ 2400 rpm

Engine Management:

Multi-Point Fuel Injection (MPFI) with Electronic Control Unit (ECU)

Fuel Type:

Unleaded gasoline (87 octane recommended)

Fuel Pump Pressure:

31-39 PSI (214-269 kPa)

🔧 Transmission

Transmission Options:

4-speed automatic (AW4), 5-speed manual (AX-5, AX-4)

Transfer Case Options:

2-speed part-time (NP231 Command-Trac), 2-speed full-time (NP242 Selec-Trac)

Aw4 Features:

Electronically controlled, known for durability and smooth shifting.

Ax5 Features:

Robust 5-speed manual for trailering and off-road control.

Aw4 Fluid Type:

Dexron III Automatic Transmission Fluid (ATF)

Ax5 Fluid Type:

GL-3 or GL-4 Gear Oil (75W-90 recommended)

📐 Dimensions

Wheelbase:

101.4 inches (2575 mm)

Length:

169.5 inches (4305 mm)

Width:

70.2 inches (1783 mm)

Height:

63.1 inches (1603 mm)

Curb Weight Range:

Approximately 3200-3500 lbs (1451-1588 kg), depending on configuration

Cargo Volume Behind Rear Seat:

Approx. 31.7 cu ft (0.90 m³)

Cargo Volume With Rear Seat Folded:

Approx. 71.4 cu ft (2.02 m³)

🛡️ Safety Features

NHTSA Rollover Resistance:

3 out of 5 stars (as rated for SUVs of its era)

Braking System:

Front ventilated disc brakes, rear drum brakes. Optional ABS (Anti-lock Braking System) on some models.

Seatbelts:

Front shoulder belts with integrated lap belts, rear lap belts.

Body Construction:

Unibody construction with integrated roll cage elements.

💡 Technology Features

Audio System:

Factory AM/FM stereo with cassette player, optional CD player, and speaker configurations ranging from 4 to 6 speakers.

Dash Design:

Functional and driver-oriented dashboard with clear analog gauges for speedometer, tachometer (on some models), fuel, temperature, and oil pressure.

ABS:

Optional Anti-lock Braking System (ABS) available on front and rear wheels depending on trim and drivetrain.

Early Tech:

Basic power accessories (windows, locks, mirrors on higher trims), cruise control.

🔧 Maintenance

Oil Change Interval:

Every 3,000 - 5,000 miles (4,800 - 8,000 km) or 6 months, whichever comes first.

Transmission Fluid Change Interval:

Every 30,000 - 60,000 miles (48,000 - 96,000 km), depending on driving conditions.

Spark Plug Replacement Interval:

Approximately 30,000 miles (48,000 km) for standard plugs, potentially longer for platinum or iridium.

Engine Oil Spec:

SAE 10W-30 API SG or higher (for both 4.0L and 2.5L engines)

Engine Coolant Capacity:

Approx. 12 quarts (11.4 liters) for 4.0L, 9 quarts (8.5 liters) for 2.5L

Coolant Type:

Ethylene Glycol based coolant (50/50 mix with distilled water)

Brake Fluid Type:

DOT 3

Common Problems:

Head gasket leaks (especially on early 4.0L models), cracked cylinder heads (pre-1991 but can affect some later ones), rust (especially on rockers, floor pans, and rear quarter panels), TPS (Throttle Position Sensor) failure, CPS (Crankshaft Position Sensor) failure, AW4 transmission electronic issues.

Rust Prone Areas:

Rocker panels, rear wheel arches, floor pans, tailgate.

4.0L Engine Common Faults:

Oil pressure sender failure, valve cover gasket leaks, intake manifold gasket leaks.

📚 Vehicle History

Jeep Legacy:

Jeep's heritage is rooted in rugged, go-anywhere capability, established with the Willys MB during WWII. The Cherokee nameplate has a long lineage of off-road vehicles.

Xj Introduction:

The XJ Cherokee, introduced in 1984, revolutionized the SUV market with its pioneering unibody construction, offering a lighter, more car-like ride than traditional body-on-frame SUVs. The 1991 model year saw significant updates including standard MPFI for both engines and revised interior and exterior styling.

Production Era:

1984-2001 (North America), production for the 1991 model year was within the second generation of the XJ platform.

Manufacturing Location:

Toledo, Ohio, USA

🏆 Awards & Recognition

Offroad Magazine Recognition:

Consistently ranked as a top off-road vehicle by automotive publications for its class and capability.

Consumer Reports Rating:

Historically received favorable ratings for its powertrain and off-road performance, though some years noted potential reliability concerns in specific areas.