What size rotors are on a 2018 Subaru Forester?

On the 2018 Subaru Forester, rotor size varies by engine and brake package. The most common configuration for the non-turbo 2.5-liter models uses 11-inch front rotors and 10-inch rear rotors, while the turbocharged 2.0-liter XT models employ larger rotors.

Rotor sizes by engine and trim

The following factory specifications reflect the core trims in the 2018 Forester lineup. These sizes are given in inches and their metric equivalents for quick reference.

• 2.5L non-turbo models (Base, Premium, Limited, Touring): Front rotors 11.0 inches (279 mm) in diameter; Rear rotors 10.0 inches (254 mm) in diameter.


• 2.0L turbo models (XT): Front rotors around 12.0–12.2 inches (305–310 mm) in diameter; Rear rotors around 11.0–11.5 inches (279–292 mm) in diameter.

Note: Actual rotor sizes can vary slightly depending on the exact brake package and any factory or dealership specifications. Verify with official sources for your exact vehicle.

How to verify the rotor size for your specific Forester

To confirm the precise rotor dimensions for your individual vehicle, use these methods:

• Check the owner's manual or the brake system specifications section for the exact rotor sizes.


• Inspect the rotor stamping or labeling on the rotor edge or hub area, if visible.


• Consult the Subaru official parts catalog or a dealer portal using your VIN to pull the exact rotor size and part numbers.


• Measure directly with the wheel removed: use calipers or a tape measure to determine the front and rear rotor diameters.


• When purchasing replacements, match the size to your current rotors or rely on a technician to confirm compatibility for your VIN.

For the most precise information, especially if your Forester has an unusual brake package or aftermarket components, contact a Subaru dealer with your VIN to retrieve the exact rotor dimensions and part references.

Summary

In summary, the typical 2018 Forester with the 2.5L engine uses 11-inch front rotors and 10-inch rear rotors, while the 2.0L XT turbo model uses larger rotors (roughly 12 inches front and about 11 inches rear). Always verify the exact size for your vehicle via the owner's manual, VIN-based Subaru parts catalogs, or a certified dealer to ensure correct replacement parts.

What is the most common problem with the 2018 Subaru Forester?

The 2014-2018 Subaru Foresters' common problems include failure-prone transmission, burning oil, rear spring failure and short-lived wheel bearings.

Are 203mm rotors better than 180mm?

Rotor size affects your bike's braking efficiency and safety. Larger rotors like the 203mm provide more stopping power and better heat management, which is important for heavier bikes or aggressive riding. Smaller rotors, such as the 180mm, are lighter and sufficient for most riders.

How do I tell what size my rotors are?

To measure a rotor's size, find its diameter by measuring across its center with a tape measure or caliper, and its thickness by using a micrometer or caliper at multiple points on the friction surface. For the most accurate measurements, remove the rotor from the vehicle first. 
This video demonstrates how to measure the rotor's diameter without removing it: 33sSouthSideMobileBrakeService.YouTube · Feb 18, 2025
Measuring rotor diameter

• Method 1: Measure with the wheel removed 
  • Use a tape measure or a large caliper. 
  • Measure from one outer edge of the rotor straight across to the opposite outer edge, ensuring the measurement goes through the exact center. 
• Method 2: Measure with the wheel on
  • Use a large caliper or a method using a paper template with a hole for the hub to make an imprint on the paper, then measure the imprint. 
  • Another method is to use two magnetic markers attached to the rotor's surface and a tape measure to measure the distance between the magnets. 

Measuring rotor thickness

• Method 1: Measure with the wheel removed 
  • Use a micrometer or a caliper. 
  • Measure the thickness at several different points along the friction material of the rotor to account for wear. 
• Method 2: Measure with the wheel on
  • Use a small caliper to measure the thickness in a few spots on the rotor's surface. 

Other important measurements

• Hat height: With the rotor upside down on a flat surface, measure the distance from the base to the start of the friction material. 
• Runout: Use a dial indicator to check for runout, which is an indicator of rotor wobble. 

You can watch this video to learn how to measure brake rotor thickness: 58sDriver's TherapyYouTube · Jul 9, 2025

What size rotors are on a 2018 Forester?

Notes: Rotor only, 316 mm rotor.