The 1987 GMC Sierra Repair Manual provides comprehensive guidance for maintaining and repairing the 1987 GMC Sierra truck series. This manual covers engine systems (including 4.3L V6, 5.0L V8, and 5.7L V8 engines), transmission (4-speed manual, 5-speed manual, and 3-speed automatic), braking system, suspension, electrical systems, fuel system, cooling system, and routine maintenance procedures. Below are key sections for specifications, maintenance schedules, troubleshooting, and repair procedures.
Key specifications for 1987 GMC Sierra models including engine options, transmission types, and chassis details.
| Specification | Details |
|---|---|
| Engine Options | 4.3L V6, 5.0L V8, 5.7L V8 |
| Transmission | 4-speed manual, 5-speed manual, 3-speed automatic |
| Fuel System | Carbureted (standard), TBI available on select models |
| Brake System | Front disc, rear drum with power assist |
| Suspension | Independent front, leaf spring rear |
| Wheelbase | 117.5" (short bed), 131.5" (long bed) |
| Fuel Capacity | 20 gallons (standard), 34 gallons (optional) |
| Gross Vehicle Weight | 4,600 - 6,200 lbs depending on configuration |
| Electrical System | 12-volt negative ground |
| Cooling System | 16-18 quart capacity with pressure cap |
Regular maintenance schedule and procedures for optimal vehicle performance.
WARNING! Always disconnect battery before performing electrical work. Use jack stands when working under vehicle.
Diagnostic and repair procedures for 4.3L, 5.0L, and 5.7L engines.
CAUTION! Allow engine to cool before removing radiator cap. Use proper safety equipment.
Manual and automatic transmission service procedures.
Front disc and rear drum brake service and repair.
Front Disc Brakes: Pad replacement, rotor inspection, caliper service. Rear Drum Brakes: Shoe replacement, wheel cylinder inspection, adjustment.
Brake Specifications: Front pad thickness minimum 1/8", rotor thickness minimum 1.125", rear shoe lining minimum 1/16".
Front and rear suspension components and steering system maintenance.
Tip: Always torque suspension bolts to specification with vehicle at normal ride height.
12-volt electrical system diagnosis and repair.
Battery: Group 24, 12-volt, 550 CCA. Alternator: 63-amp output. Starter: Direct drive type.
Carburetor and fuel delivery system service.
Supports both carbureted and TBI fuel systems.
WARNING! No smoking or open flames when working on fuel system. Have fire extinguisher available.
Radiator, water pump, and thermostat service.
Cooling Capacity: 16-18 quarts with heater. Thermostat: Opens at 195°F. Pressure Cap: 15 psi.
| Symptom | Possible Cause | Corrective Action |
|---|---|---|
| Engine won't start | Fuel, spark, or compression issue | Check fuel delivery, spark plugs, compression test |
| Poor fuel economy | Carburetor adjustment, timing | Adjust carburetor, check ignition timing |
| Overheating | Coolant level, thermostat, water pump | Check coolant, replace thermostat, test water pump |
| Brake pull | Stuck caliper, contaminated pads | Inspect calipers, replace pads, check alignment |
| Electrical issues | Battery, alternator, grounds | Test charging system, clean battery terminals |
Reset: Disconnect battery for 30 minutes to reset computer if equipped.
Service: Refer to GMC dealership for complex electrical diagnostics.
Complete electrical schematics for 1987 GMC Sierra.
Includes starting circuit, charging circuit, lighting system, ignition system, and accessory wiring. Diagrams show wire colors, connector locations, and circuit protection devices.
Note: Use multimeter for circuit testing. Refer to color codes: BLK-black, RED-red, WHT-white, BLU-blue, YEL-yellow, GRN-green, BRN-brown, ORG-orange.