2025 Volvo VNL Fluid Type Specs

Quick Reference

Fluid	Type/Spec	Capacity
Engine Oil	SAE 15W-40, 10W-30 (Volvo VDS-4.5, API CK-4)	~45 quarts / 11.25 gallons (Volvo D13TC)
Engine Coolant	Volvo VCS-2 (OAT, yellow)	~14-16 gallons
Transmission Fluid	Volvo I-Shift (Volvo 97318) / Eaton PS-387	~12-16 quarts
Rear Axle / Differential	SAE 75W-90, 80W-90 (Volvo 97312)	~16-22 pints
Brake Fluid	DOT 4	Varies
Power Steering Fluid	ATF (Volvo 97332)	~2-3 quarts
Windshield Washer Fluid	-	~2 gallons
Diesel Exhaust Fluid (DEF)	ISO 22241	~23-26 gallons

Engine Oil

For the 2025 Volvo VNL equipped with the D13TC engine, the recommended engine oil is a heavy-duty diesel engine oil meeting Volvo VDS-4.5 specification and API service category CK-4. The most commonly used viscosity grades are SAE 15W-40 for general use and SAE 10W-30 for improved fuel economy and cold-weather performance. Always use a reputable brand that explicitly lists the VDS-4.5 approval on the bottle. Using a non-approved oil can lead to increased wear, deposit formation, and potential damage to the complex aftertreatment systems. Oil change intervals should be based on the truck's duty cycle and the manufacturer's recommendations, but a typical interval is around 50,000 miles for long-haul applications.

Engine Coolant

The 2025 Volvo VNL uses a specific Organic Acid Technology (OAT) coolant called Volvo VCS-2. This is a yellow-colored, long-life coolant designed to provide excellent protection for the cooling system's various metals. It is critical to never mix VCS-2 with other coolant types, such as conventional green or Hybrid OAT (HOAT) coolants. Mixing coolants can cause them to gel, leading to blockages, overheating, and expensive damage to the engine and radiator. When topping off or refilling the system, use only pre-mixed VCS-2 or a concentrate mixed with distilled water to the proper ratio (typically 50/50).

Transmission Fluid

For models equipped with the Volvo I-Shift automated manual transmission, the correct fluid is one meeting Volvo 97318 specification. For those with an Eaton automated manual, use a fluid meeting Eaton PS-387 specification. These are specialized fluids designed for the unique demands of these transmissions. Using a generic ATF will lead to poor shifting, overheating, and premature clutch and gear wear.

Rear Axle / Differential Fluid

The rear axles on a 2025 Volvo VNL require a high-quality gear oil meeting Volvo 97312 specification. The most common viscosity grades are SAE 75W-90 and SAE 80W-90. These are typically synthetic gear oils designed for long life and excellent protection under heavy loads. Always check the specific axle model and refer to the service information for the exact fluid and capacity.

Brake Fluid

The air brake system on a Class 8 truck like the VNL does not use "brake fluid" in the traditional sense of a passenger car's hydraulic brake system. The air brake system uses compressed air. However, there may be hydraulic clutch components that use DOT 4 brake fluid.

Power Steering Fluid

The power steering system in the 2025 VNL typically uses an automatic transmission fluid (ATF) meeting Volvo 97332 specification. Using the correct fluid is essential for smooth steering operation and to prevent damage to the pump and steering gear.

Windshield Washer Fluid

Use any commercially available windshield washer fluid. For winter use, select a fluid with a low freezing point to prevent damage to the reservoir and lines.

Diesel Exhaust Fluid (DEF)

For the selective catalytic reduction (SCR) system to function correctly, the 2025 Volvo VNL requires high-quality Diesel Exhaust Fluid (DEF) that is certified to ISO 22241 and API CK-4. Use of contaminated or low-quality DEF can lead to costly damage to the SCR system. The DEF tank is typically located on the driver's side of the vehicle and has a blue cap.

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