2015 Toyota Tundra Fluid Specs

Quick Reference

Fluid	Type/Spec	Capacity
Engine Oil	SAE 0W-20 (API SN / ILSAC GF-5)	7.9 - 8.5 qt (4.6L/5.7L V8)
Engine Coolant	Toyota Super Long Life Coolant (SLLC)	12.3 - 17.2 qt
Transmission Fluid	Toyota ATF WS	~12.2 qt (service refill)
Transfer Case Fluid	SAE 75W-90 GL-5 Gear Oil	~1.1 - 1.6 qt
Front Differential Fluid	SAE 75W-90 GL-5 Gear Oil	~2.2 qt
Rear Differential Fluid	SAE 75W-90 GL-5 Gear Oil	3.8 - 4.4 qt
Brake Fluid	DOT 3	As needed
Power Steering Fluid	ATF DEXRON® II or III	~1.3 qt
Windshield Washer Fluid	Summer/Winter Blend	~1.3 gal

Engine Oil

For the 2015 Toyota Tundra, the required engine oil is SAE 0W-20. This low-viscosity oil is critical for ensuring proper lubrication, fuel economy, and cold-start performance in the Tundra's 4.6L (1UR-FE) and 5.7L (3UR-FE) V8 engines. The oil must meet or exceed API Service SN or ILSAC GF-5 specifications. Using a different viscosity, such as 5W-20 or 5W-30, can lead to decreased fuel efficiency and may affect engine performance. Always look for the API "starburst" and "donut" symbols on the bottle to confirm the oil meets these standards.

Capacity varies slightly by engine and configuration:

• 4.6L V8 (1UR-FE): Approximately 7.9 quarts (7.5 liters) with a filter change.
• 5.7L V8 (3UR-FE): Approximately 8.5 quarts (8.0 liters) with a filter change.

Given the large oil capacity, it is crucial to verify the level on the dipstick after filling. The recommended change interval is typically every 10,000 miles or 12 months under normal driving conditions, but should be shortened to 5,000 miles if the vehicle is used for towing, off-roading, or frequent short trips.

Engine Coolant

Toyota specifies its proprietary Super Long Life Coolant (SLLC) for the 2015 Tundra. This is a pink, ethylene-glycol based coolant with a hybrid organic acid technology (HOAT) formulation. It is crucial not to mix SLLC with other coolant types, especially conventional green or orange OAT (Organic Acid Technology) coolants. Mixing chemistries can cause the coolant to gel, leading to blockages in the radiator, heater core, and cooling passages, which can cause severe engine damage from overheating.

If you are servicing the system, use only Toyota SLLC or a compatible pink HOAT coolant that explicitly meets Toyota’s specifications. The factory fill is a 50/50 mixture of coolant concentrate and deionized water, which provides protection down to -34°F (-37°C).

Total system capacity ranges from 12.3 to 17.2 quarts depending on the engine and equipment. The factory-fill coolant is designed to last up to 100,000 miles for the first service, with subsequent changes recommended every 50,000 miles.

Transmission Fluid

The 6-speed automatic transmission in the 2015 Tundra requires Toyota ATF WS (World Standard) fluid. This is a specific, low-viscosity synthetic fluid. Using any other type of ATF, such as Dexron, Mercon, or even older Toyota fluids like Type T-IV, will lead to shifting problems, transmission shudder, and eventual component failure. There is no "universal" ATF that is a suitable substitute for genuine ATF WS.

This transmission is a "sealed" unit, meaning it does not have a traditional dipstick for checking the fluid level. Checking the level is a complex process involving specific fluid temperatures and an overflow plug, which should be left to a qualified technician. A complete fluid exchange requires approximately 12.2 quarts, though a simple drain-and-fill will use significantly less. Toyota considers this a "lifetime" fluid, but many technicians recommend a fluid and filter service every 60,000 to 90,000 miles, especially for trucks that tow or operate in harsh conditions.

Transfer Case & Differential Fluid

For 4WD models, the transfer case and front/rear differentials require a high-quality gear oil.

• Transfer Case Fluid: The specification is SAE 75W-90 GL-5 Gear Oil. Capacity is approximately 1.1 to 1.6 quarts. Some owners prefer to use a full synthetic 75W-90 for improved cold-weather performance and longevity.

• Front Differential Fluid: The front differential also calls for SAE 75W-90 GL-5 Gear Oil. The capacity is approximately 2.2 quarts.

• Rear Differential Fluid: The rear differential uses SAE 75W-90 GL-5 Gear Oil. Capacity varies from 3.8 to 4.4 quarts. An important note: if your Tundra is equipped with a limited-slip differential (LSD), you must use a gear oil that is formulated for LSDs or add a friction modifier additive. Failure to do so will cause the clutch packs in the differential to chatter and wear out prematurely.

Service intervals for these components are typically every 30,000 miles, but should be checked more frequently if the vehicle is used for water-fording or heavy-duty applications.

Brake Fluid & Power Steering Fluid

• Brake Fluid: The 2015 Tundra’s hydraulic brake system requires DOT 3 brake fluid. While DOT 4 fluid has a higher boiling point and is compatible, it is also more hygroscopic (absorbs moisture faster) and is not necessary for stock applications. Never use DOT 5 fluid, as it is silicone-based and completely incompatible with the system. Brake fluid should be flushed and replaced every 2-3 years or 30,000 miles, as its performance degrades over time due to moisture absorption.

• Power Steering Fluid: The hydraulic power steering system uses Automatic Transmission Fluid DEXRON® II or III. Do not use ATF WS or any other type of dedicated power steering fluid unless it explicitly states compatibility with Dexron. The system capacity is approximately 1.3 quarts.

Washer Fluid

The windshield washer reservoir has a large capacity of approximately 1.3 gallons (5 liters). Use a quality, commercial washer fluid appropriate for the climate. In winter, use a fluid with a low freezing point to prevent lines and nozzles from freezing. In summer, a bug-remover formula can be effective.

Find a trusted shop on Repairius.