🏷️ Basic Information

Make:

Jeep

Model:

Cherokee

Model Codes:

YJ, XJ

Year:

1991

👋 Introduction

Segment:

Compact SUV / Off-road Vehicle

Target Audience:

DIY enthusiasts, independent repair shops, Jeep owners seeking detailed service information.

Competitors 1991:

Ford Explorer, Chevrolet S-10 Blazer, Toyota 4Runner, Nissan Pathfinder.

Jeep Advantage:

Renowned off-road capability, robust construction, iconic design, strong aftermarket support.

Iconic Design:

The XJ Cherokee, launched in 1984, was revolutionary as the first SUV with a unibody construction, offering a lighter, more rigid, and comfortable ride compared to body-on-frame competitors.

Off Road Prowess:

Despite its compact size and unibody, the Cherokee (especially YJ and XJ variants) maintained Jeep's legendary off-road capability with available 4x4 systems and solid axles (front and rear).

Durability:

Known for its sturdy construction and reliable powertrains, making it a favorite for demanding conditions.

Manual Value Proposition:

Provides in-depth, manufacturer-level data essential for maintaining and repairing this highly capable vehicle.

📋 Manual Details

Engine Coverage:

All gasoline engines

Transmission Coverage:

Manual and Automatic Transmissions

Chassis Systems Coverage:

Suspension, Steering, Brakes, Driveline

Electrical Systems Coverage:

Wiring Diagrams, Lighting, Ignition, Starting, Charging, Accessories

Body And Interior Coverage:

Body Panels, Doors, Windows, Seats, Dashboard

Estimated Pages:

1000+

Type:

Service and Repair Manual

Language:

English

Format:

Downloadable Digital File (PDF)

📖 Manual Coverage

Engine Mechanical:

Disassembly, inspection, assembly, troubleshooting for all major engine components (cylinder head, block, pistons, crankshaft, camshaft, timing systems).

Engine Performance:

Fuel injection systems, ignition timing, emissions control, cooling system, lubrication system, engine diagnostics.

Transmission Manual:

Clutch system, gear shifting mechanisms, transmission fluid service, internal component inspection and repair.

Transmission Automatic:

Torque converter, valve body, planetary gear sets, hydraulic controls, transmission fluid service, electronic controls, troubleshooting.

Driveline And Axles:

Front and rear differentials, transfer case (NV242, NV231), drive shafts, U-joints, CV joints, axle bearings and seals.

Suspension System:

Front and rear suspension (leaf springs, coil springs, solid axles), shock absorbers, bushings, ball joints, steering linkage.

Steering System:

Power steering pump, steering gear, steering column, tie rods, drag link, alignment procedures.

Brake System:

Front disc brakes, rear drum brakes (or optional rear discs), master cylinder, brake booster, ABS (if equipped), brake fluid service, bleeding procedures.

Electrical System:

Battery, charging system (alternator), starting system (starter motor), ignition system, lighting (headlights, taillights, interior), instrumentation, fuses, relays, power windows, locks, mirrors, wiper system.

Fuel System:

Fuel tank, fuel pump, fuel filter, fuel injectors, fuel lines, evaporative emissions system (EVAP).

Cooling System:

Radiator, water pump, thermostat, coolant hoses, fan clutch, heater core, AC system (basic components).

Exhaust System:

Exhaust manifolds, catalytic converter, muffler, exhaust pipes, O2 sensors.

Body And Frame:

Body panel removal/installation, door mechanisms, window regulators, tailgate, rust repair considerations, chassis inspection.

Interior Trim:

Dashboard removal, seat removal, headliner, door panels, carpet replacement.

Maintenance Procedures:

Oil changes, filter replacements, spark plug replacement, fluid checks and changes, belt inspections and replacement, brake pad replacement, tire rotations.

Troubleshooting:

Diagnostic flowcharts for common problems (e.g., starting issues, poor performance, electrical faults).

Repair Procedures:

Detailed step-by-step instructions for component removal, installation, and adjustment for all major systems.

Rebuilding Procedures:

Instructions for rebuilding engines, transmissions, and differentials.

Wiring Diagrams:

Comprehensive electrical schematics for all vehicle systems.

Alignment Specifications:

Front and rear wheel alignment angles and specifications.

Depth Level:

Comprehensive from basic maintenance to major component overhauls and diagnostics.

Diagnostic Tools:

Information on using basic diagnostic tools, OBD-I codes (where applicable), and visual inspections.

Special Tools:

Identification of any specialized tools required for specific repair procedures.

📊 Manual Specifications

Format:

PDF (Portable Document Format)

Searchable Text:

Yes (typically included in professionally digitized manuals)

Printable:

Yes

Quality:

High-resolution digital reproduction of original factory documentation

Binding:

N/A (Digital Download)

Paper Quality:

N/A (Digital Download)

⚙️ Engine Specifications

Engine Code 1:

4.0L Inline-6 OHV (242 ci)

Engine Description 1:

High Output (HO) version introduced in 1987, known for its torque and durability.

Engine Code 2:

2.5L Inline-4 OHV (150 ci)

Engine Description 2:

Economical option, common in base models.

4.0L Horsepower:

182 hp @ 4,600 rpm (approx.)

4.0L Torque:

220 lb-ft @ 3,000 rpm (approx.)

2.5L Horsepower:

121 hp @ 4,800 rpm (approx.)

2.5L Torque:

145 lb-ft @ 3,200 rpm (approx.)

Fuel Delivery:

Multi-port Fuel Injection (MPI) for 4.0L, Throttle Body Injection (TBI) or MPI for 2.5L depending on early/late 1991 production.

Fuel Type:

Unleaded Gasoline

Ignition System:

Distributorless Ignition System (DIS) or distributor-based ignition, depending on engine and emission controls.

🔧 Transmission

Transmission Type Std:

5-Speed Manual (AX-5 for 2.5L, AX-15 for 4.0L)

Transmission Type Opt:

3-Speed Automatic (AW-4)

Transmission Type Opt 2:

4-Speed Automatic (less common for 1991, but possible late model updates)

Transfer Case Std:

Selec-Trac (NV242) - Part-time 2WD/4WD

Transfer Case Opt:

Command-Trac (NV231) - Part-time 2WD/4WD with optional low-range gearing.

Clutch Type:

Dry single plate (for manual transmissions)

Manual Transmission Fluid:

API GL-4 SAE 75W-90 or 80W-90 gear oil (check specific transmission type for precise recommendation)

Automatic Transmission Fluid:

Chrysler ATF+3 (or equivalent Dexron III/Mercon compatible fluid)

Transfer Case Fluid:

NP231: ATF Dexron II/III; NP242: ATF Dexron II/III

📐 Dimensions

Wheelbase Xj:

101.4 inches (2576 mm)

Wheelbase Yj:

93.4 inches (2372 mm) (YJ is the Wrangler, XJ is the Cherokee. This manual covers both, but the YJ refers to the Wrangler. This product name implies Cherokee YJ XJ, which is a common colloquialism for the XJ Cherokee, as YJ is the Wrangler chassis. The manual is likely for the XJ Cherokee primarily.)

Length Xj:

167.4 inches (4252 mm)

Width Xj:

69.4 inches (1763 mm)

Height Xj:

63.0 inches (1600 mm)

Cargo Volume Xj Behind Front Seats:

Approx. 69 cu ft

Cargo Volume Xj Behind Rear Seats:

Approx. 31 cu ft

Curb Weight Xj Est:

3,100 - 3,600 lbs (depending on configuration)

Towing Capacity Xj Est:

Up to 5,000 lbs (with proper equipment and engine)

Wheel Bolt Pattern:

5x4.5 inch (5x114.3 mm)

Tire Size Std Xj:

P215/75R15 (common on base models)

Tire Size Opt Xj:

P225/75R15 or P235/75R15 (common on higher trims or with optional wheels)

🛡️ Safety Features

NHTSA Frontal Impact Rating Driver:

Not rated or 3-star equivalent (for 1991 models, often lacked advanced testing standards)

NHTSA Frontal Impact Rating Passenger:

Not rated or 3-star equivalent

Active Braking:

Front disc brakes, Rear drum brakes. ABS was optional and not standard on all trims.

Stability Control:

Not available on 1991 models.

Airbags:

Driver-side airbag became standard in 1994. Not standard on 1991 models. Passenger airbags not available.

Seat Belts:

Three-point front seat belts, lap belts for rear passengers.

Rollover Protection:

Reinforced windshield frame and integrated sport bar (part of unibody structure) contribute to rollover protection, particularly on the Wrangler YJ, but the XJ also benefits from its unibody rigidity.

💡 Technology Features

Audio System:

AM/FM stereo, optional cassette player, optional CD player (rare for '91). Speakers typically 4 or 6.

Display:

Analog gauges for speedometer, tachometer (optional), fuel, temperature. Warning lights for oil pressure, battery, brake system.

Cruise Control:

Optional on most trims.

Anti Lock Brakes:

Optional, not standard on all models.

Connectivity Features:

None (modern connectivity like Bluetooth, USB, or smartphone integration was not available).

Power Accessories:

Optional power windows, power door locks, power mirrors on higher trims.

🔧 Maintenance

Oil Change Interval Engine Oil:

3,000-5,000 miles or 6 months, whichever comes first (recommend 5W-30 or 10W-30)

Filter Replacement Oil Filter:

Replace with every oil change.

Spark Plug Replacement:

Approx. 30,000 miles (depending on plug type)

Coolant Flush Interval:

Every 2-3 years or 30,000 miles

Transmission Fluid Change Auto:

30,000-60,000 miles (depending on driving conditions)

Transmission Fluid Change Manual:

50,000-100,000 miles

Engine Oil Capacity 4.0L:

5 US quarts (with filter)

Engine Oil Capacity 2.5L:

4 US quarts (with filter)

Coolant Type:

Ethylene Glycol based antifreeze (green) for 1991. Capacity: Approx. 10-12 US quarts.

Brake Fluid Type:

DOT 3

Power Steering Fluid:

ATF Dexron II/III or Mopar power steering fluid

Common Issue 1:

Radiator leaks (especially around plastic end tanks)

Common Issue 2:

Oil filter adapter housing leaks (common on 4.0L)

Common Issue 3:

Transfer case chain stretch or wear

Common Issue 4:

Cracked exhaust manifolds (especially on 4.0L)

Common Issue 5:

Heater core failure (leading to interior leaks and fogging)

Common Issue 6:

Sway bar link wear (leading to clunking noises)

Common Issue 7:

Rust formation, particularly on fenders, rocker panels, and tailgate

📚 Vehicle History

Jeep Legacy:

Jeep's heritage traces back to World War II with the Willys MB, establishing a reputation for ruggedness and off-road capability.

Xj Introduction:

The XJ Cherokee was introduced in 1984 and became a groundbreaking vehicle for its unibody construction, pioneering the modern SUV segment.

Yj Introduction:

The YJ Wrangler (1987-1995) replaced the CJ series and featured a redesign including rectangular headlights and a coil spring suspension in the front (replacing leaf springs).

1991 Updates:

Minor updates for 1991 included refinements to the 4.0L engine, potential introduction of new features or trim levels. The manual covers the comprehensive state of the XJ/YJ for this model year.

Xj Production Years:

1984-2001

Yj Production Years:

1987-1995

Manufacturer:

American Motors Corporation (AMC) until 1987, then Chrysler Corporation after acquisition.

🏆 Awards & Recognition

Off Road Magazine Ranking:

The XJ Cherokee was frequently praised for its off-road prowess by automotive publications, often outperforming larger and more expensive competitors in its class.

Vehicle Of The Year Awards:

While specific 'Vehicle of the Year' awards for the 1991 model year might be less documented, the XJ Cherokee consistently received accolades for its overall design, capability, and value throughout its lifecycle.

Long Term Durability Reputation:

The 4.0L 'six-pack' engine, in particular, gained a reputation for exceptional longevity and reliability, making the XJ a sought-after vehicle for off-road use and long-term ownership.