1987 Mighty Max Service Manual

The 1987 Mighty Max is a compact pickup truck manufactured by Mitsubishi Motors, featuring a 2.0L or 2.6L gasoline engine, 5-speed manual transmission, rear-wheel drive, and payload capacity up to 1,400 lbs. This service manual covers maintenance procedures, specifications, troubleshooting, and repair guidelines for engine, transmission, brakes, suspension, electrical systems, and body components. Below are key sections for technical specifications, maintenance schedules, repair procedures, and troubleshooting.

1. Vehicle Specifications 2. Maintenance Schedule 3. Engine System 4. Transmission & Drivetrain 5. Brake System 6. Suspension & Steering 7. Electrical System 8. Body & Interior 9. Troubleshooting Guide 10. Wiring Diagrams 11. Technical Service Bulletins

Vehicle Specifications

Key technical data for 1987 Mighty Max models including engine options, dimensions, and capacities.

SpecificationDescription
Engine Options2.0L 4G63 / 2.6L 4G54 inline-4
Transmission5-speed manual / 3-speed automatic optional
DrivetrainRear-wheel drive
Payload Capacity1,400 lbs maximum
Fuel Capacity15.9 gallons
Wheelbase108.7 inches
Overall Length176.4 inches
Curb Weight2,645 lbs (2.0L model)
Brake SystemFront disc / rear drum
SuspensionIndependent front / leaf spring rear

Maintenance Schedule

Recommended service intervals for optimal vehicle performance and longevity.

  1. Oil and filter change: Every 3,000 miles or 3 months
  2. Air filter replacement: Every 15,000 miles
  3. Spark plugs: Replace every 30,000 miles
  4. Coolant flush: Every 30,000 miles or 2 years
  5. Brake fluid: Replace every 30,000 miles or 2 years
  6. Transmission fluid: Check every 15,000 miles
  7. Timing belt: Replace every 60,000 miles

WARNING! Always use manufacturer-recommended fluids and parts. Follow torque specifications precisely.

Engine System

Service procedures for 2.0L and 2.6L gasoline engines including tune-up specifications.

  1. Compression test: Should read 150-170 psi (minimum 120 psi)
  2. Valve clearance: 0.008 in (cold) for intake, 0.010 in (cold) for exhaust
  3. Ignition timing: 5° BTDC at 750 rpm
  4. Idle speed: 750 ± 50 rpm (manual), 700 ± 50 rpm (automatic)
  5. Fuel pressure: 36-40 psi at idle

CAUTION! Disconnect battery before servicing electrical components. Allow engine to cool before opening cooling system.

Transmission & Drivetrain

Brake System

Hydraulic brake system service including specifications and adjustment procedures.

Front Brakes: Disc, rotor diameter 10.2 inches, pad thickness minimum 0.08 inches

Rear Brakes: Drum, diameter 9.0 inches, shoe thickness minimum 0.04 inches

Master cylinder: Tandem type, reservoir capacity 0.6 liters. Brake pedal free play: 0.04-0.12 inches. Parking brake: Mechanical, rear wheels only, adjustment at equalizer.

Suspension & Steering

Front independent suspension with torsion bars, rear leaf spring system.

  1. Front suspension: Upper/lower control arms, torsion bars, stabilizer bar
  2. Rear suspension: Semi-elliptical leaf springs, hydraulic shocks
  3. Steering: Recirculating ball type, 3.5 turns lock-to-lock
  4. Wheel alignment: Toe-in 0.08 ± 0.08 inches, camber 0°30' ± 45'
  5. Tire pressure: 28 psi front, 32 psi rear (standard load)

Tip: Always check suspension components for wear during tire rotation.

Electrical System

12-volt negative ground system with alternator and battery specifications.

  1. Battery: 12V, 45Ah minimum, group size 24
  2. Alternator: 55 amp output, regulator internal
  3. Starter: 1.4 kW reduction gear type
  4. Fuse box: Located under dashboard, 10 fuses total
  5. Bulb types: Headlight 60/55W, tail/stop 21/5W, turn signal 21W
  6. Ignition system: Electronic with magnetic pickup
  7. Charging voltage: 13.5-14.5 volts at 2000 rpm

WARNING! Disconnect battery before electrical work. Use circuit tester for diagnosis.

Body & Interior

Body dimensions, interior components, and maintenance procedures.

Troubleshooting Guide

Common problems and diagnostic procedures for various systems.

SymptomPossible CauseCorrective Action
Engine won't startFuel, spark, or compression issueCheck fuel delivery, spark plugs, ignition timing, compression
Poor fuel economyDirty air filter, misadjusted carburetorReplace air filter, adjust carburetor mixture, check timing
Brake pullStuck caliper, contaminated padsInspect calipers, replace pads, flush brake fluid
Transmission noiseLow fluid, worn bearingsCheck fluid level, inspect for metal particles
Electrical failureBad alternator, corroded connectionsTest charging system, clean battery terminals

Reset: Disconnect battery for 10 minutes to reset ECU if equipped.

Wiring Diagrams

Complete electrical schematics for starting, charging, lighting, and accessory systems.

Technical Service Bulletins

Manufacturer-issued updates and corrections for known issues.

TSB 87-15: Revised carburetor adjustment procedure for high-altitude operation. TSB 87-22: Updated clutch master cylinder part number. TSB 87-31: Improved alternator bracket design to reduce belt slippage. For latest bulletins, contact Mitsubishi dealer with VIN.

1987 Mighty Max Service Manual © - All Rights Reserved 2025