1988 International Truck Manual

The 1988 International Truck Manual provides comprehensive technical information, maintenance procedures, and operational guidelines for International Harvester trucks manufactured in 1988. This manual covers engine systems, transmission, braking, electrical systems, chassis, and routine maintenance schedules for various International truck models from that year. Below are key sections for specifications, maintenance, troubleshooting, and operational procedures.

1. Vehicle Specifications 2. Engine Systems 3. Transmission & Drivetrain 4. Braking System 5. Electrical System 6. Chassis & Suspension 7. Routine Maintenance 8. Operational Procedures 9. Troubleshooting Guide 10. Parts & Service Information 11. Safety Precautions

Vehicle Specifications

Key specifications for 1988 International Truck models including engine options, dimensions, and capacity ratings.

SpecificationDescription
Engine OptionsDT466 diesel, 7.3L V8 diesel, 6.9L IDI diesel
Horsepower Range170-230 HP depending on engine configuration
Transmission5-speed manual, 6-speed manual, Allison automatic options
GVWR16,000-33,000 lbs depending on model
Wheelbase134-254 inches
Fuel Capacity50-100 gallons
Cab ConfigurationConventional cab, crew cab options
Braking SystemAir brakes standard on heavier models
Electrical System12-volt DC, negative ground
SuspensionLeaf spring front and rear

Engine Systems

Detailed information on engine components, maintenance procedures, and specifications.

  1. DT466 Diesel Engine: In-line 6 cylinder, 466 cubic inches, turbocharged option
  2. Fuel System: Rotary injection pump, mechanical governor
  3. Cooling System: Belt-driven water pump, radiator maintenance
  4. Lubrication System: Full-flow oil filtration, recommended oil types
  5. Air Intake System: Dry air cleaner with restriction indicator

WARNING! Engine components operate at high temperatures; allow cooling before servicing. Use proper safety equipment.

Transmission & Drivetrain

Transmission types, maintenance intervals, and drivetrain components.

  1. Manual Transmission: Spicer 5-speed and 6-speed models
  2. Automatic Transmission: Allison AT-545 4-speed automatic
  3. Clutch System: Single plate, hydraulic actuation
  4. Drive Shaft: Two-piece with center support bearing
  5. Rear Axle: Single and tandem axle configurations

CAUTION! Ensure transmission is in neutral and parking brake engaged before servicing.

Braking System

Electrical System

12-volt electrical system with alternator and battery specifications.

Components: 75-amp alternator, maintenance-free batteries, circuit breakers.

Starting System: 12-volt starter motor, solenoid activation. Charging System: Internal regulator alternator. Lighting: Sealed beam headlights, incandescent marker lights. Instrument Panel: Analog gauges for speedometer, tachometer, fuel, temperature, oil pressure, air pressure.

Chassis & Suspension

Frame construction and suspension components maintenance.

  1. Frame: Ladder-type construction with C-channel rails
  2. Front Suspension: Multi-leaf springs with shock absorbers
  3. Rear Suspension: Multi-leaf springs with helper springs
  4. Steering System: Recirculating ball gear, hydraulic power assist
  5. Wheels & Tires: 10-hole disc wheels, tube-type tires standard

Tip: Regular inspection of suspension components for wear and proper torque.

Routine Maintenance

Scheduled maintenance intervals and procedures.

  1. Engine Oil Change: Every 7,500 miles or 250 hours
  2. Fuel Filter Replacement: Every 15,000 miles
  3. Air Filter Service: Check restriction gauge monthly
  4. Coolant Change: Every 24 months or 100,000 miles
  5. Transmission Fluid: Check level weekly, change every 50,000 miles
  6. Grease Points: Lube every 5,000 miles or 3 months
  7. Brake Inspection: Check linings every 12,000 miles
  8. Wheel Bearing: Repack every 50,000 miles

WARNING! Use only recommended fluids and filters. Improper maintenance can void warranty.

Operational Procedures

Daily pre-trip inspection and operating guidelines.

Troubleshooting Guide

Common operational issues and diagnostic procedures.

SymptomPossible CauseCorrective Action
Engine won't startFuel, electrical, or battery issuesCheck fuel supply, battery voltage, starter operation
Poor engine performanceAir/fuel restrictionInspect air filter, fuel filters, injection timing
Transmission shifting hardLow fluid, linkage adjustmentCheck fluid level, adjust shift linkage
Brakes draggingAdjustment, air systemCheck brake adjustment, air system operation
Electrical problemsBattery, alternator, groundsTest battery, alternator output, check ground connections

Reset: Refer to specific system reset procedures in appropriate sections.

Service: Contact authorized International dealer for technical support.

Parts & Service Information

Genuine International parts recommended for optimal performance and warranty compliance.

CAUTION! Use of non-approved parts may affect vehicle performance and safety.

Safety Precautions

Important safety information for operation and maintenance.

Always use proper jack stands when working under vehicle. Disconnect batteries before electrical work. Use personal protective equipment. Follow all environmental regulations for fluid disposal. Secure vehicle with wheel chocks when servicing.

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