2015 GMC Yukon Fluid Specs & Capacities

As an ASE-certified master technician, I know that using the correct fluids is critical for the longevity and performance of your 2015 GMC Yukon. Generic "universal" fluids can lead to costly damage. This guide details the specific factory-spec fluids and capacities for your vehicle.

Quick Reference: 2015 GMC Yukon Fluid Specifications

Fluid	Type/Specification	Capacity
Engine Oil	SAE 0W-20 (dexos1 Gen 2 or newer)	8.0 quarts (7.6 liters)
Engine Coolant	ACDelco DEX-COOL Orange (GM 6277M)	16.2 - 17.4 quarts (15.3 - 16.5 liters)
Automatic Transmission Fluid	DEXRON VI	12.0 quarts (11.4 liters) - full rebuild
Transfer Case Fluid (4WD)	DEXRON VI	1.6 quarts (1.5 liters)
Front Differential Fluid (4WD)	SAE 75W-90 Synthetic Axle Lubricant (GM 9986115)	1.8 pints (0.85 liters)
Rear Differential Fluid	SAE 75W-85 Synthetic Axle Lubricant (GM 19300457)	4.2 - 5.1 pints (2.0 - 2.4 liters)
Brake Fluid	DOT 3 (GM 19299818)	As needed
Power Steering Fluid	ACDelco Power Steering Fluid (GM 19329450)	As needed
Windshield Washer Fluid	Good quality solvent	~1.0 gallon (~3.8 liters)

Engine Oil

Your 2015 Yukon's 5.3L or 6.2L V8 engine requires a full synthetic SAE 0W-20 motor oil that meets or exceeds the GM dexos1 Gen 2 specification. You may see newer specs like dexos1 Gen 3, which are backward-compatible and offer even greater protection. Using the wrong viscosity, such as 5W-30, can interfere with the engine's complex components like the Active Fuel Management (AFM) system, potentially leading to lifter failure. Always use a full synthetic oil from a reputable brand that clearly states it is licensed for dexos1. The oil capacity, including the filter, is 8.0 quarts (7.6 liters).

Engine Coolant (Antifreeze)

The cooling system must be filled with a silicate-free, Organic Acid Technology (OAT) coolant. The factory-specified coolant is ACDelco DEX-COOL Orange, which meets the GM 6277M specification. It is critical not to mix DEX-COOL with other coolant types, such as conventional green (IAT) or hybrid (HOAT) coolants found in other vehicles. Mixing can cause the coolant to gel, leading to blockages, overheating, and expensive damage to the radiator and heater core. Always top off with pre-mixed 50/50 DEX-COOL or mix concentrated DEX-COOL with distilled water. The system capacity ranges from 16.2 to 17.4 quarts depending on the specific cooling system options.

Automatic Transmission Fluid

The 6-speed (6L80) and 8-speed (8L90) automatic transmissions in the 2015 Yukon require a very specific fluid: DEXRON VI. Do not use older DEXRON III, Mercon V, or any "universal" or "multi-vehicle" ATF. Using the incorrect fluid can cause poor shifting, torque converter shudder, and premature transmission failure. A complete fluid exchange or rebuild requires approximately 12 quarts, but a simple drain-and-fill will use significantly less. It is recommended to have a professional service the transmission.

Transfer Case Fluid (4WD Models)

For four-wheel-drive Yukons, the transfer case also uses DEXRON VI automatic transmission fluid. This is a common point of confusion, as many other vehicles use gear oil or a dedicated transfer case fluid. Stick to the OEM specification to ensure proper lubrication and function of the 4WD system. The capacity is 1.6 quarts (1.5 liters).

Front & Rear Differential Fluid

Proper gear oil is essential for protecting your differentials.

• Front Differential (4WD): The front axle requires SAE 75W-90 Synthetic Axle Lubricant meeting GM specification 9986115. The capacity is 1.8 pints (0.85 liters).
• Rear Differential: The rear axle specifies SAE 75W-85 Synthetic Axle Lubricant (GM Part No. 19300457). If your Yukon has the G80 locking differential, no additional limited-slip friction modifier is needed when using the factory-spec fluid. Capacity varies slightly based on the axle housing, from 4.2 to 5.1 pints (2.0 to 2.4 liters). Always fill to the bottom of the fill plug hole.

Brake & Power Steering Fluid

• Brake Fluid: The hydraulic brake system requires a standard DOT 3 motor vehicle brake fluid, such as ACDelco Part No. 19299818. Never use DOT 5 silicone-based fluid, as it is incompatible with the system's seals. The system should be bled and flushed every 2-3 years as brake fluid absorbs moisture, which reduces its boiling point and can corrode internal components.
• Power Steering Fluid: Unlike many systems that use ATF, your Yukon has a dedicated Power Steering Fluid (GM Part No. 19329450). Do not substitute with transmission fluid. Top off as needed if you notice any whining or groaning noises during turns, and inspect for leaks.

Windshield Washer Fluid

There is no complex specification here. Use any good quality commercial windshield washer solvent. In colder climates, ensure the fluid has a low freezing point to prevent damage to the reservoir and pump. The reservoir holds approximately one gallon.

Using the correct, manufacturer-specified fluids is the single most important thing you can do to ensure your 2015 GMC Yukon runs reliably for years to come. When in doubt, always verify in your owner's manual or with a trusted technician.

Find a trusted shop on Repairius.