Does Subaru Forester need premium gas?

For the vast majority of today’s Forester models, premium gasoline is not required; regular 87-octane fuel is sufficient and can save you money. Premium might have been recommended for older turbocharged variants, but it isn’t needed for the current lineup.

Current fuel requirements in the United States

The standard Forester in North America uses a 2.5-liter naturally aspirated engine. Subaru’s official guidance for this engine is regular unleaded gasoline (87 octane). Using higher-octane fuel does not provide a meaningful performance or efficiency boost under normal driving conditions.

• 2.5-liter naturally aspirated engine (the common Forester variant today): Regular unleaded gasoline (87 octane) is sufficient and premium is not required.

In practice, most Forester owners can confidently choose 87-octane fuel and save on fueling costs, while keeping an eye on any knocking or pinging indications and consulting the manual if symptoms arise.

Historical context: turbocharged Foresters

Earlier generations of the Forester offered a turbocharged 2.0-liter engine (often referred to as the Forester XT). Those turbo models typically required premium gasoline (higher octane, often 91 octane or higher) to prevent knocking and to sustain peak performance. The current U.S. Forester lineup does not rely on that turbo engine, so premium is generally unnecessary for today’s models.

• Forester XT / 2.0L Turbo (older generations): Premium gasoline (around 91 octane or higher) was typically recommended or required.

For owners of older turbo-equipped Foresters, follow the requirements in your specific model year’s manual. For current U.S. models, regular 87-octane fuel remains the standard.

Practical tips for drivers

Use these guidelines to ensure you meet the correct fuel specification and avoid unnecessary costs:

1. Check your exact model year and engine variant in the owner's manual or Subaru’s official regional materials to confirm the octane requirement.


2. For the current Forester with the 2.5L engine, opt for regular gasoline (87 octane). Premium fuel does not offer a meaningful advantage in normal driving.


3. If you notice knocking, pre-ignition, or reduced performance, avoid assuming higher octane will fix it; instead consult a dealer to diagnose engine health and fuel delivery issues.

Overall, most Forester owners should stick with regular gasoline. Reserve premium for older turbo variants or cases where the manual explicitly calls for it in your region.

Summary

The Subaru Forester does not require premium gasoline for its current 2.5-liter engines in North America; regular 87-octane fuel is appropriate and cost-effective. Premium fuel may have been necessary for older turbocharged Forester XT models, but today’s lineup does not require it. Always verify your specific engine and octane recommendation in the owner's manual or Subaru’s regional guidance to ensure you meet the correct requirements for your model year and location.

Do Subaru Foresters need premium gas?

Regular fuel: Models such as the Forester, Outback, and Crosstrek run efficiently on regular unleaded or 87-octane fuel. Using higher-octane fuel in these vehicles won't harm the engine, but it doesn't offer any benefit in terms of performance.

What if I accidentally put 89 instead of 87?

What happens if you use a higher octane gas than is recommended? If you opt for a higher octane than your manual recommends—say, 89 instead of 87—your car will be perfectly fine. It will not, however, improve your car's mileage or give it any sort of extra performance boost.

Do subarus run better on premium gas?

Regular gasoline has an octane level of 87 or so, while premium gasoline has an octane level of 90 or above. This can be a huge advantage for luxury and performance cars specifically, like the Subaru WRX and BRZ.

What is the most common problem with the Subaru Forester?

The most common problem with the Subaru Forester is the continuously variable transmission (CVT), which can suffer from issues like shuddering, delayed acceleration, and whining noises, and may require expensive repairs. Other frequent issues include problems with the engine (especially oil consumption), the electrical system, and, in certain model years, issues with windshields cracking and batteries dying quickly.
 
You can watch this video to learn more about Subaru Forester common problems: 51scar PROblemsYouTube · Feb 19, 2024
Transmission (CVT)

• Shuddering and jerking: This often occurs when accelerating from a stop.
• Delayed acceleration and slipping: The engine revs up but the car doesn't speed up as expected, which can be dangerous when merging.
• High-pitched whining: This can be a sign of worn pulley bearings inside the transmission.
• Repair cost: CVTs are often not rebuildable and require a complete, expensive replacement. 

Engine

• Excessive oil consumption: Many model years, particularly from the 2014-2018 generation, are known for burning through oil rapidly.
• Oil leaks: Leaks, often requiring expensive engine replacements, are another reported problem. 

Electrical and other issues

• Electrical malfunctions: Issues can range from infotainment system glitches and GPS errors to more serious problems like a battery dying prematurely or the EyeSight safety system turning off unexpectedly. 
• Air conditioning (AC): Some models experience AC failure that can be costly to fix. 
• Windshields: In the 2019-2024 generation, windshields can crack from small chips. 
• Airbag malfunctions: Older models, such as the 2009-2011, have been associated with malfunctioning airbags. 

This video explains some of the most common issues with the Subaru Forester, including the transmission and engine: 57sGear GazetteYouTube · Oct 23, 2025