Positioning:
The Jeep Cherokee (XJ) in 1991 was a highly regarded compact SUV, known for its off-road capability, ruggedness, and relatively affordable price point. It competed with vehicles like the Toyota 4Runner, Nissan Pathfinder, and Ford Explorer. This manual caters to owners and technicians seeking to maintain or repair this iconic vehicle.
Analysis:
The 1991 model year represents a mature iteration of the XJ platform, which had been in production since 1984. It benefited from incremental updates and refinements over the years, solidifying its reputation for durability and off-road prowess. The manual's focus on this specific year ensures detailed information relevant to the technologies and configurations of that era.
Features:
The 1991 Cherokee XJ is characterized by its unibody construction (a significant innovation at the time for SUVs), its legendary Selec-Trac and Command-Trac 4x4 systems, and its distinctive boxy styling. This manual will detail the intricacies of these unique features.
Powertrain:
Engine mechanical, fuel system, cooling system, exhaust system, transmission (manual and automatic), transfer case, driveline, axles.
Chassis:
Suspension (front and rear), steering system, brake system (front and rear), wheels and tires.
Electrical:
Battery, charging system, starting system, ignition system, lighting system, instrument cluster, power accessories, body control modules, engine control module (ECM) diagnostics.
Body:
Body construction, interior trim, exterior trim, doors, windows, seats, climate control system, heating and ventilation.
Maintenance:
Scheduled maintenance, lubrication, fluid changes, filter replacements, inspections.
Diagnosis:
Troubleshooting charts, diagnostic procedures for electrical and mechanical systems, fault code interpretation.
Repair:
Detailed step-by-step repair procedures for all major vehicle components, including disassembly, cleaning, inspection, repair, and reassembly.
Overhaul:
Complete engine and transmission overhaul procedures, including torque specifications, clearances, and assembly sequences.
Installation:
Procedures for installing and adjusting various components, including suspension, steering, and accessories.
Depth:
Comprehensive, from basic adjustments and fluid checks to complete engine and transmission rebuilds, electrical system diagnostics, and bodywork repairs.
Engine Options:
4.0L (242 cu in) Inline-6 OHV (AMC 242) and 2.5L (150 cu in) Inline-4 OHV (AMC 150)
Horsepower:
Approx. 190 hp @ 4,750 rpm
Torque:
Approx. 220 lb-ft @ 3,250 rpm
Horsepower:
Approx. 125 hp @ 4,800 rpm
Torque:
Approx. 150 lb-ft @ 2,400 rpm
Fuel Delivery:
Multi-port fuel injection (MPI) for 4.0L; Throttle body injection (TBI) or MPI for 2.5L depending on specific sub-model.
Engine Codes:
4.0L: R, P; 2.5L: P (for TBI), K (for MPI)
Coolant Type:
Ethylene Glycol based, 50/50 mix with distilled water (refer to manual for exact Mopar specification).
Manual Transmission:
AX-5 5-speed manual (common with 2.5L and some 4.0L)
Automatic Transmission:
AW4 4-speed automatic (common with 4.0L), 32RH 3-speed automatic (less common for 1991, but variants existed)
Transfer Case Options:
Command-Trac (part-time 4WD), Selec-Trac (full-time 4WD with part-time option).
Automatic Transmission Fluid:
ATF+3 or equivalent (Chrysler spec, refer to manual for exact part number/spec).
Manual Transmission Fluid:
GL-3 or GL-4 gear oil (refer to manual for specific viscosity and approval).
Wheelbase:
101.4 inches (2575 mm)
Length:
Approx. 169.9 inches (4315 mm)
Width:
Approx. 70.2 inches (1783 mm)
Height:
Approx. 63.7 inches (1618 mm)
Curb Weight:
Approx. 3,000-3,500 lbs (1360-1588 kg), varies by configuration.
Towing Capacity:
Varies by engine and configuration, typically 2,000-3,500 lbs.
Cargo Volume:
Approx. 31.7 cu ft behind rear seat, 67.3 cu ft with rear seat folded.
NHTSA Rollover Resistance:
N/A (Pre-2000s rating system, often not directly comparable)
Braking System:
Front disc brakes, rear drum brakes. Optional Anti-lock Braking System (ABS) on rear wheels.
Steering Type:
Power-assisted recirculating ball steering.
Airbags:
Driver-side airbag became standard for 1991.
Seat Belts:
Front and rear seat belts, shoulder belts for front occupants.
Audio System:
Basic AM/FM radio with cassette player. Optional premium sound systems. Aftermarket head units are very common upgrades.
ABS:
Optional rear-wheel ABS available on some models.
OBD Ii:
Not OBD-II compliant. Uses an older OBD-I diagnostic system with a specific connector (refer to manual for location and diagnostic procedures).
Engine Control Module:
Chrysler's 'RENIX' engine management system (prior to the introduction of OBD-II in later years). Diagnostics often involve reading flash codes.
Oil Change Interval:
Every 3,000 miles or 3 months, whichever comes first (typical recommendation for this era).
Oil Filter Part Number:
Mopar: MO-090 or equivalent (e.g., Fram PH8A, Wix 51515).
Engine Oil Type:
API SG or higher, SAE 10W-30 (preferred for 4.0L and 2.5L in most climates, check manual for specific temperature ranges).
Engine Oil Capacity:
4.0L: 5 quarts (4.7L); 2.5L: 4 quarts (3.8L) with filter (refer to manual).
Coolant Capacity:
Approx. 10.5 quarts (9.9L) for 4.0L, slightly less for 2.5L (with heater).
Brake Fluid Type:
DOT 3 or DOT 4.
Power Steering Fluid:
ATF+3 or equivalent (Chrysler spec).
Common Problems:
Heater core leaks, cracked exhaust manifolds (especially on 4.0L), TPS (Throttle Position Sensor) failure, CPS (Crankshaft Position Sensor) failure, automatic transmission issues (AW4 torque converter clutch), rust and corrosion.
Spark Plugs:
4.0L: Champion RC12LYC or equivalent; 2.5L: Champion RC10LYC or equivalent (verify gap).
Ignition Timing:
Static timing is set by distributor position; ECM controls dynamic timing. Refer to manual for precise procedure.
Jeep Legacy:
Jeep has a rich heritage dating back to World War II, known for its rugged, go-anywhere vehicles. The Cherokee (XJ) extended this reputation into the civilian SUV market.
Xj Generation:
The XJ generation of the Cherokee (1984-2001) was a groundbreaking vehicle, credited with pioneering the compact SUV segment and introducing unibody construction to this class. The 1991 model year received some updates including standard driver's side airbag and minor styling tweaks.
Manufacturing Location:
Toledo, Ohio, USA
Production Years Xj:
1984-2001
Off Road Magazine:
The Cherokee XJ platform, including models from this era, was frequently praised by off-road publications for its capability and aftermarket support.
Consumer Reports:
While specific ratings for 1991 may vary, the XJ generation generally received good marks for its durability and utility, though sometimes with caveats regarding early electronic issues.