How often should I change the coolant on my Highlander?

In most Highlander models, you should plan for a coolant change around 100,000 miles or 10 years, whichever comes first, when using Toyota-approved long-life coolant. If your vehicle uses a different coolant or operates under severe conditions, check the owner’s manual or ask a Toyota service technician for the precise interval.

What the official maintenance schedule says

Toyota’s maintenance guidance for the Highlander typically lists coolant replacement at 100,000 miles or 10 years under normal driving conditions, assuming the use of Toyota’s long-life coolant. The exact interval can vary by model year and engine type, so it’s important to confirm with your specific vehicle’s manual or a dealer.

If you’re unsure about the coolant type currently in your system, or if you have a model year with different specifications, have a certified technician verify the correct coolant and service interval.

Typical interval scenarios

Before detailing the scenarios, it helps to note how the interval is commonly presented in owner resources.

• Long Life Coolant (Toyota-approved): Replacement is usually recommended at 100,000 miles or 10 years, whichever comes first, under normal driving conditions.


• Conventional or non-Toyota coolant: The service interval may differ; consult your manual or a technician for the correct interval for your coolant type.

Bottom line: For most Highlanders using Toyota’s long-life coolant, plan a coolant change around the 10-year/100,000-mile mark, but always verify for your exact model year and coolant type.

Factors that can shorten coolant life

While the standard interval serves as a baseline, several factors can shorten how long coolant lasts. Consider these when planning service intervals or inspections.

• Extreme temperatures or frequent towing, which place additional stress on the cooling system.


• Coolant contamination from leaks, rust, oil intrusion, or improper mixing.


• Using the wrong coolant type or a failing cooling-system component (radiator cap, thermostat, water pump).


• Inaccurate service practices, such as improper dilution or incomplete system flushing.

Conclusion: If you drive in harsh conditions or notice signs of trouble, have the cooling system checked sooner and follow professional guidance on replacement timing.

Maintaining coolant health and preparing for a service

Keeping coolant in good condition helps prevent overheating and engine damage. Here are recommended steps to prepare for a coolant service.

1. Check your owner’s manual for the exact coolant specification for your year and engine.


2. Use only Toyota-approved coolant or an equivalent meeting Toyota’s standards.


3. Ensure the system is flushed and refilled with the correct 50/50 mix of coolant and distilled water unless pre-diluted.


4. Inspect for leaks in hoses, radiator, radiator cap, and water pump; repair any leaks before flushing if found.


5. Have the service performed by a trained technician to ensure no air pockets and proper pressure testing after refill.

Conclusion: Proper preparation and using the right coolant type are key to a successful and enduring cooling-system service.

Signs your coolant may need replacing

Even with scheduled maintenance, be alert for indicators that the coolant system may require service sooner than planned.

• Overheating or rising engine temperature on the gauge.


• Visible leaks or puddles under the vehicle.


• Discolored, sludgy, or oily coolant in the reservoir or radiator.


• Unusual sweet smell around the engine bay, suggesting coolant leakage or contamination.


• Frequent coolant loss or need to top off coolant between services.

Conclusion: If you notice any of these signs, schedule a cooling-system inspection promptly to determine whether a coolant change or other repairs are needed.

What to do if you notice overheating or leaks

If overheating occurs or you detect a leak that could indicate coolant loss, stop driving when it’s safe, check coolant levels if possible, and contact a Toyota service center. Driving with degraded or low coolant can cause severe engine damage.

Summary

The standard guideline for most Toyota Highlander models is to replace coolant at about 100,000 miles or 10 years, using Toyota-approved long-life coolant. Always verify the exact interval for your model year and coolant type in the owner’s manual or with a dealer. Severe driving conditions, leaks, or contamination can shorten this interval, so regular inspections and prompt service when issues arise are essential. Regular maintenance—paired with the correct coolant and proper service—helps prevent overheating and protects the engine over the long term.

How often should you change the coolant in a Toyota Highlander?

every two years
Typically, you should have your Toyota Highlander coolant flush completed every 30,000 miles or every two years.

How often does Toyota recommend changing coolant?

Toyota's coolant change interval depends on the coolant type, but generally, it's every 30,000 miles or 3 years for older "red" coolant, and the first change is at 100,000 miles or 5 years for newer "pink" super long life coolant, with subsequent changes every 50,000 miles or 5 years. Always check your specific vehicle's owner's manual for the exact interval and type of coolant to use. 
Coolant type and intervals
This video explains how to change coolant on Toyota cars: 22sThe Car Care NutYouTube · Aug 3, 2024

• Red Coolant: Used before 2003/2004. Replace every 30,000 miles or 3 years. 
• Pink Super Long Life Coolant: Introduced around 2003/2004. 
  • First replacement: 100,000 miles or 5 years. 
  • Subsequent replacements: Every 50,000 miles or 5 years. 
• Other coolants: Some newer vehicles may use different types, such as the 2020 Supra which has a 150,000-mile interval. Check your owner's manual. 

General recommendations

• Check your owner's manual: The most accurate information will be in your vehicle's owner's manual, as intervals can vary by model and year. 
• Follow whichever comes first: Whether it's mileage or time, get the service done when you reach the first of the two intervals.
• Flush vs. drain-and-fill: A full coolant flush removes old coolant and sediment from the system. A drain-and-fill only replaces the fluid that is drained, leaving some old coolant in the system. Some manufacturers recommend a full flush at the initial replacement interval, followed by drain-and-fills every 50,000 miles thereafter. 

How long will Toyota coolant last?

Toyota coolant life depends on the type: factory-fill pink super long life coolant can last up to 100,000 miles or 10 years, but many sources recommend changing it every 5 years or 50,000 miles after the first change. Older red or conventional coolants have a much shorter life and should be changed every 30,000 miles or two years. Always check your owner's manual for the specific recommendation for your vehicle. 
This video explains how long coolant lasts and why it should be changed regularly: 54sMercie J Auto Care, llcYouTube · Nov 30, 2023
For pink "Super Long Life" coolant

• First change: The initial factory fill can last up to 10 years or 100,000 miles. 
• Subsequent changes: After the first change, it's recommended to change it more frequently to prevent corrosion. 
  • Recommendation 1: Change every 5 years or 50,000 miles. 
  • Recommendation 2: Change every 60,000 miles or 5 years. 
  • Reasoning: Coolant degrades over time and can become acidic, potentially damaging engine seals and parts like the water pump. 

For older "red" conventional coolant

• Recommendation: Change every 30,000 miles or every two years. 

General maintenance tips

• Check the coolant level and condition every 15,000 miles or at every service interval. 
• Your owner's manual is the best source for specific maintenance intervals for your vehicle. 
• Always use Toyota-specified coolant to avoid compatibility issues and ensure proper protection. 

You can watch this video to learn how to maintain your Toyota's coolant and what type to use: 1mThe Car Care NutYouTube · Jul 20, 2020

Is a coolant flush really necessary?

Yes, a coolant flush is necessary for routine preventive maintenance, as it removes debris and old, degraded coolant that can cause overheating, corrosion, and expensive engine damage over time. It cleans out rust and scale deposits, restores the coolant's ability to transfer heat efficiently, and prevents the buildup of acidic and contaminated fluid in the cooling system. 
You can watch this video to see why coolant flushes are important for your car's engine: 58sWhat Dennis DoesYouTube · Nov 15, 2018
Why a coolant flush is necessary

• Prevents engine overheating: Coolant can become contaminated with rust and scale, which can clog passages and block the system's ability to transfer heat. A flush removes these blockages and replaces old coolant with fresh fluid. 
• Protects against corrosion: Over time, coolant becomes acidic, which can corrode metal components in the engine and radiator. Flushing the system removes acidic fluid and replaces it with new coolant that contains anti-corrosive additives. 
• Maintains the effectiveness of coolant: Coolant contains additives that break down over time. A flush replaces old, ineffective coolant with new fluid, ensuring proper freeze protection and heat transfer. 
• Prevents costly repairs: By preventing overheating, corrosion, and clogs, a regular coolant flush helps avoid catastrophic and expensive engine damage. 
• Identifies underlying issues: A flush provides an opportunity for a mechanic to inspect the system. If oil or other contaminants are found in the old coolant, it can indicate other problems that need to be addressed. 

This video demonstrates how to perform a coolant flush: 30sChrisFixYouTube · Mar 6, 2015
When to get a coolant flush

• According to your manufacturer's schedule: Check your owner's manual for the recommended service intervals. 
• If you buy a used car: It is especially important to flush the coolant if you don't know the service history of a high-mileage used car. 
• If you notice signs of a problem: Look for signs of overheating, or if you find low coolant levels and suspect a leak or contamination.