2018 Chevrolet Silverado 1500 Fluid Type Specs

Quick Reference

Fluid	Type/Spec	Capacity
Engine Oil	0W-20, API SN, dexos1® Gen 2	6.0 qt (4.3L V6) / 8.0 qt (5.3L & 6.2L V8)
Engine Coolant	ACDelco DEX-COOL® (Orange)	15.1 qt (4.3L) / 16.6 qt (5.3L) / 17.2 qt (6.2L)
Transmission Fluid	DEXRON® VI Automatic Transmission Fluid	~12.4 qt (6-speed) / ~11.2 qt (8-speed) - Service fill varies
Transfer Case Fluid	DEXRON® VI Automatic Transmission Fluid	~1.6 qt
Front Differential	SAE 75W-90 Synthetic Gear Oil	~1.75 qt
Rear Differential	SAE 75W-90 Synthetic Gear Oil	~2.4 qt (9.5") / ~2.75 qt (9.76")
Brake Fluid	DOT 3 Hydraulic Brake Fluid	As needed
Power Steering	Electric Power Steering (EPS) - No Fluid	N/A
Windshield Washer	GM Optikleen® Washer Fluid or equivalent	As needed

Engine Oil Specifications

The 2018 Silverado 1500 is factory-spec'd for SAE 0W-20 viscosity grade engine oil. This is a full synthetic oil that must meet General Motors' stringent dexos1® Gen 2 specification. Using an oil that meets this spec is critical for the proper function of the engine's complex systems, including variable valve timing and active fuel management (AFM).

While other oils might be API SN or SP certified, the dexos1® certification includes proprietary tests by GM to ensure maximum protection against sludge, piston deposits, and oil aeration, which is vital for the longevity of modern GM V6 and V8 engines.

• 4.3L V6 (LV3): 6.0 quarts (5.7 liters)
• 5.3L V8 (L83): 8.0 quarts (7.6 liters)
• 6.2L V8 (L86): 8.0 quarts (7.6 liters)

Common Pitfalls: Do not use a heavier viscosity oil like 5W-30 unless explicitly stated for extreme conditions in your owner's manual. Sticking to the 0W-20 dexos1® Gen 2 spec is the best way to ensure proper lubrication and fuel economy. Change intervals are determined by the Oil Life Monitoring (OLM) system, but a good rule of thumb is to check the oil level at every fuel fill and change it when the monitor indicates.

Engine Coolant / Antifreeze

All 2018 Silverado models use a specific Organic Acid Technology (OAT) coolant known as DEX-COOL®. This coolant is easily identifiable by its orange color. It is a long-life coolant, typically lasting up to 5 years or 150,000 miles, but always consult your service manual for precise intervals.

When topping off or refilling the system, it is crucial to use either pre-mixed DEX-COOL® 50/50 or a concentrate mixed with distilled water. Do not use tap water, as it contains minerals that can cause scaling and deposits within the radiator and cooling passages.

Common Pitfalls: Never mix DEX-COOL® with other coolant types, such as the green Inorganic Additive Technology (IAT) or yellow/gold Hybrid Organic Acid Technology (HOAT) coolants. Mixing chemistries can cause the coolant to gel, leading to clogged radiators, heater cores, and catastrophic engine overheating. If you are unsure what is in the system, a complete flush and fill with the correct fluid is recommended.

Transmission Fluid

Depending on the specific configuration, your 2018 Silverado will have either a 6-speed or an 8-speed automatic transmission. Both transmissions require DEXRON® VI Automatic Transmission Fluid (ATF). This is a full synthetic fluid with specific frictional properties designed for modern GM transmissions.

• 6-Speed Automatic (6L80): Service fill is typically around 6.0 quarts, with a total system capacity of 12.4 quarts.
• 8-Speed Automatic (8L90): Service fill is around 5.5-6.5 quarts, with a total system capacity of 11.2 quarts.

Common Pitfalls: Do not use "universal" or multi-vehicle ATF unless it explicitly states that it meets the DEXRON® VI specification. Using the wrong fluid can lead to harsh shifts, chattering, and premature transmission failure. Fluid capacity can vary significantly based on whether you are doing a simple pan drop or a full fluid exchange. Always verify the level using the transmission dipstick/check plug procedure outlined in the OEM service information.

Transfer Case & Differential Fluids

For 4WD models, the transfer case and differentials require specific gear oils to protect them under load.

• Transfer Case: The transfer case in the 2018 Silverado is lubricated with DEXRON® VI ATF, the same fluid used in the automatic transmission. This simplifies service, but it's critical not to confuse it with traditional gear oil. Capacity is approximately 1.6 quarts.

• Front Differential: The front axle requires SAE 75W-90 Synthetic Gear Oil.

• Rear Differential: The rear axle also uses SAE 75W-90 Synthetic Gear Oil. The 2018 Silverado uses a mechanical locking rear differential (G80) which does not require a limited-slip additive. Using an additive when it is not required can interfere with the locker's operation.

Common Pitfalls: Using a heavier gear oil like 75W-140 is not recommended unless you are consistently towing at maximum capacity in extreme heat, and even then, you should consult OEM service info. The most common error is adding a friction modifier to the rear differential, which is unnecessary for the G80 locker.

Brake and Other Fluids

• Brake Fluid: The hydraulic brake system requires DOT 3 motor vehicle brake fluid. You can also use DOT 4, as it is compatible and has a higher boiling point, but it is not required. Never use DOT 5 (silicone-based) fluid, as it is incompatible with the system's seals. Brake fluid should be changed every 2-3 years as it is hygroscopic, meaning it absorbs moisture from the air.

• Power Steering Fluid: The 2018 Silverado 1500 is equipped with Electric Power Steering (EPS). This system uses an electric motor to provide steering assistance, and therefore does not have any power steering fluid to check or change.

• Windshield Washer Fluid: Use any quality washer fluid, but for freezing temperatures, use a winter-grade fluid with de-icing properties. GM offers its own Optikleen® brand, but any reputable brand will suffice.

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