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1988 GMC Truck R-Series Truck

Factory specifications, fluid capacities, torque values, EPA fuel economy and the federal safety record for the 1988 R-Series Truck.

The 1988 GMC Truck R-Series Truck takes 5 qt of 20W-20 engine oil.

Quick specs

Fluid capacities, tune-up values and fuel economy at a glance.

Engine oil capacity5 qtOEM · verified

Engine oil type20W-20 / 20W-40 / 20W-50OEM · verified

Fitment & sizes

Replacement part sizes and factory part numbers — battery, bulbs, filters and belts.

From the factory this vehicle uses OE oil filter 25160561. Note the factory fuel filter is now discontinued — plan on a superseded or quality aftermarket equivalent, which the part pages below list where known. Each part links to every other vehicle that shares it, so a part you already stock may fit more of your fleet than you'd expect.

OE service part numbers OEM · verified

Engine oil filter	25160561 alt 12708762
Engine air filter	06484235 alt 08996118
Fuel filter	25171792 discontinued · alt 5651803
Spark plug	19302741 alt 19300382
Front wiper blades	15184702 alt 12363297
Serpentine belt	09433769 alt 09433775
Thermostat	14077122 alt 10105135

Service quick specs OEM factory data

Capacities, torques and tune-up values from the factory service manual.

This engine holds 5 qt of 20W-20 / 20W-40 / 20W-50 engine oil, 80W-90 · GL-5 in the differential, DOT 3 brake fluid.

Lubricants & capacities

Brake Fluid	DOT 3
Differential Gear Oil	80W-90 · GL-5
Differential Gear Oil Capacity	4.2 qt
Differential Gear Oil	80W-90 · GL-5
Differential Gear Oil Capacity	27.0 qt
Engine Coolant	ETHYLENE GLYCOL
Engine Oil	20W-20 · 20W-40 · 20W-50 · 15W-40 · 5W-30
Engine Oil Capacity	5 qt

Factory maintenance schedule OEM · verified

Normal service, condensed from the factory interval matrix.

Under the factory schedule, replace the engine oil and filter every 5,000 mi; spark plugs every 12,000 mi.

At 5,000 mi	Drive Axle Assembly (drain & refill)
Every 5,000 mi	Brake System (inspect) · Engine Oil Filter (replace) · Shift Linkage (lubricate) · Steering System (inspect) · Suspension System (inspect) · Transmission Assembly (inspect)
At 6,000 mi	Drive Axle Assembly (drain & refill) · Engine Oil Filter (replace)
Every 6,000 mi	Accessory Drive Belt (inspect) · Body Latches, Locks & Hinges (inspect) · Brake Line (inspect) · Brake Linings (inspect) · Differential (inspect fluid level) · Engine Oil (drain & refill)
At 7,500 mi	Tire & Wheel Assembly (rotate)
Every 12,000 mi	Air Cleaner Manifold Heat Control Actuator (inspect) · Engine Oil Filter (replace) · Radiator Fan Assembly (inspect) · Spark Plugs (replace) · Underbody Splash Shield (inspect) · Universal Vehicle Operation (inspect idle speed)
Every 15,000 mi	CV Joint Boot (inspect) · Driveshaft U-Joint (lubricate) · Tire & Wheel Assembly (rotate)
At 24,000 mi	Universal Vehicle Operation (inspect idle speed)
Every 24,000 mi	Air Intake System (inspect) · Carburetor Mounting Fasteners (inspect) · Drive Axle Assembly (drain & refill) · EGR System (inspect) · Early Fuel Evaporation System (inspect) · Engine Air Filter Element (replace)

Common OBD-II trouble codes

The most common OBD-II codes for this vehicle's emissions system. These are standardized SAE J2012 definitions, not vehicle-specific fault reports.

P0420

Catalyst system efficiency below threshold — Bank 1

P0300

Random / multiple cylinder misfire detected

P0171

System too lean — Bank 1

P0455

Evaporative emission system leak detected — large leak

P0128

Coolant thermostat below regulating temperature

P0442

Evaporative emission system leak detected — small leak

VIN tools

Decode factory build data for a specific vehicle by VIN.

VIN

Decode a VIN to confirm the transmission and build data for a specific R-Series Truck. OEM

Build data

Plant, GVWR class, engine and body data for any 17-character VIN.

Recalls

Check open recall campaigns against a specific vehicle by VIN.

Vehicles with shared specs

Find every vehicle that shares this one's battery, bulbs, oil capacity, platform or parts.

Vehicles taking 5 qt Engine oil filter 25160561 Engine air filter 06484235 Fuel filter 25171792 Spark plug 19302741

Reference guides

Cross-vehicle references for the kinds of data on this page.

OBD-II trouble codes Maintenance schedules Fluid capacities & specs

Frequently asked

How much oil does the 1988 R-Series Truck take?

5 qt of ABOVE 40 degrees F 30, ABOVE 20 degrees F: 20W-20, 20W-40, 20W-50, ABOVE 10 degrees F: 15W-40, BELOW 60 degrees F: 5W-30, per the factory manual.