Most Sienna motorists prefer lower-octane gasoline to save costs, but this fuel choice results in low engine performance and engine damage.
Now, if you need to know the ideal gas for a Toyota Sienna, our guide below will shed more light.
I’ve compiled this guide to share detailed insights about what type of gas the Toyota sienna takes. You will also see the gas type of Toyota Sienna by year and how much it costs to fill the tank.
What Type of Gas Does A Toyota Sienna Take?
All Toyota Sienna generations from 1997 to 2021 can use regular unleaded gasoline to run their 2.5L hybrid engine, 3.0L, 3.3L, or 3.5L V6 engines. (1)
Regular unleaded gasoline with octane ratings of 87-90 is suitable for Siennas with a 2.5L hybrid engine, 3.0L, 3.3L, or 3.5L V6.
Premium gas with octane ratings does not offer any added advantage to Siennas. But 2003-2021 Toyota Siennas can run on premium fuel with an octane rating of 91-92.
The premium fuel gives better gas mileage due to the higher octane ratings than the regular unleaded counterpart. It also helps minimize the risk of pre-ignition inside hot engine cylinders.
Regular unleaded gasoline is suitable for a Toyota Sienna with a low engine compression ratio since it does not need to produce more power. The octane rating of 87-90 is ideal for the engine.
But if your Toyota Sienna has a higher engine compression ratio, use premium unleaded gasoline since it produces more power. The fuel is also ideal for Siennas with large and powerful engines.
Both premium and regular unleaded gas are combustible. But regular unleaded fuel will burn faster than its premium unleaded counterpart.
Toyota recommends running Siennas on premium gasoline to amplify the horsepower and performance. But I recommend accessing the engine compression ratio and performance needs.
What Type of Gas Should You Not Use on Toyota Sienna?
Toyota sienna displays the gasoline specifications near the fuel cap to avoid making mistakes on the gas type. Every Toyota Sienna model has a unique engine type with different fuel requirements.
Filling the tank with correct fuel specifications will help increase horsepower and performance. Besides that, it will also help reduce the risk of long-term engine damages not covered in the warranty.
Below are the types of gas you should not use on Toyota sienna (2):
Gasoline without Additives
Low-quality gasoline will affect the engine’s performance, efficiency, and lifespan. Gasoline without additives will make your sienna engine vulnerable to corrosion and mineral deposits.
Toyota recommends gasoline with additives to clean the fuel system and prevent corrosion and metal deposits in the engine. It will also boost the performance and improve engine lifespan.
Unadjusted Seasonal Gasoline
An unadjusted seasonal gas will make your engine struggle to enhance combustion. The issue will make your Toyota sienna experience low horsepower and performance.
I recommend visiting a busy gas station when the season change since the seasonal fuel adjustment is inevitable. A well-blended fuel is ideal for any weather condition.
The fuel is ideal for diesel engines that generate more power. Adding diesel gas to your Toyota Sienna will shut down and damage the engine.
Toyota sienna engines cannot burn diesel fuel. Seek assistance from a professional mechanic to remove all traces of diesel gas in the engine system.
Toyota sienna engines can run on premium fuel without any problem. But the premium gas with a higher octane rating does not clean or improve the engine performance.
Premium gas has no added advantage to sienna that needs regular fuel. You will instead be spending the extra money to fill your gas tank.
Flex Fuel (E85)
Toyota Sienna has a regular gasoline engine and belongs to the non-flex fuel category. Flex-fuel can reduce your Sienna engine performance and efficiency.
The E85 will make the check engine light appear on the dashboard and cause issues with some fuel lines in your Toyota sienna.
Gas Type of Toyota Sienna by Year
This is the first generation of Toyota Sienna with 3.0L V6 engine, which is compatible with regular unleaded gas of 87 octane ratings. Toyota does not recommend using premium fuel in this engine since it does not offer any additional benefits.
It is the second generation of Toyota Sienna with a 3.3L V6 engine optimized to run on regular unleaded gasoline of 87octane rating. Siennas can also run on premium gas with an octane rating of 91 despite not offering additional benefits.
It is the thirdToyota Sienna generation with a 3.5L V6 engine compatible with regular unleaded fuel of 87 octane rating. The gasoline engine is also compatible with premium fuel of 91 octane ratings. But the premium gas does not offer additional benefits over its regular counterpart. (3)
The latest Toyota Sienna generation has a 2.5L hybrid engine that works well with regular unleaded regular gasoline of 87-90 octane ratings. The hybrid engine is also compatible with the gas of 91-92 octane ratings.
2021 Toyota Sienna Gas Type
2021 Toyota Sienna is the current generation with a 2.5L four-cylinder hybrid engine optimized to operate on regular unleaded gas of 87-90 octane ratings. (4)
But the Toyota Company recommends premium gasoline with an octane rating of 91-92 to increase the horsepower and performance of your Sienna.
The 2021 Toyota Sienna engine is compatible with regular unleaded and premium gasoline. But the engine will experience low performance and many problems with unleaded fuel.
If you are looking for better gas mileage and reduced engine problems, I recommend using premium gasoline with an octane rating of 91-92.
The high octane fuel allows your 2021 Toyota Sienna to generate more power and high performance. Avoid leaded fuel since it will damage your emission control system.
How Much does It Cost to Fill Up Toyota Sienna?
The average cost for filling the 2020 Toyota Sienna is about $64.40 since it has a fuel capacity tank of 20 gallons. (5)
The 2021 Toyota Sienna redesign reduced the fuel tank capacity to 18 gallons, and this would cost $57.96 to fill it up.
But the cost of filling a 2021 Toyota Sienna depends on your geographical location sine some states like Hawaii it may cost $73.92 and in Arkansas $51.78 to fill the Sienna up.
What’s the Toyota Sienna Gas Tank Size?
Toyota Sienna comes up in four generations with different gas tank capacities. The regular transformation helps reduce the fuel tank size and improve the car’s performance. (6)
The 1997-2003 generation has a fuel tank capacity of 20.9 gallons (74 liters) and the 2003-2020 generation has a gas tank size of 20 gallons (75 liters). The latest generation has an 18gallons fuel tank capacity.
Toyota Siennas come in four generations with different engine types. But these engines are optimized to work on regular unleaded fuel of 87-90 octane ratings.
Toyota Company recommends using high octane fuel though it does not offer additional benefits to your Sienna. But second, third, and fourth generations can use premium gasoline.
Modern Toyota Siennas have hybrid engines optimized to run on premium gasoline to boost performance and increase the engine service life.
I hope this information helped you buy the correct gas type for your Toyota Sienna. Feel free to share your experience in the comment section below.