The first-generation Forester, internally coded SF, introduced North American buyers to a then-unusual formula: a tall, wagon-shaped body sitting on a unibody chassis with genuine all-wheel drive and enough ground clearance to shrug off rough roads. Whether you’re maintaining a base L, a well-optioned S, or the turbocharged S/Turbo sold in later model years, Rolling Big Power offers tire sizing that bolts right up to the SF’s factory wheels, as well as plus-size options for owners running aftermarket alloys or mild suspension lifts.
SF Foresters shipped with four primary rim diameters depending on trim and model year: 15 inch, 16 inch, 17 inch, and 18 inch. Factory and plus-fit sizing covers 205/70R15 (26.30 x 8.07 x 15), 215/60R16 (26.16 x 8.46 x 16), 225/55R17 (26.74 x 8.86 x 17), and 235/45R18 (26.33 x 9.25 x 18). The table below shows all factory-spec tire sizes for the 1997–2002 Subaru Forester SF, with the flotation conversion alongside to make cross-shopping RBP off-road tires straightforward.
| Diameter | Standard Sizing | Flotation Sizing |
|---|---|---|
| 15 Inch | 205/70R15 | 26.30 x 8.07 x 15 |
| 16 Inch | 215/60R16 | 26.16 x 8.46 x 16 |
| 17 Inch | 225/55R17 | 26.74 x 8.86 x 17 |
| 18 Inch | 235/45R18 | 26.33 x 9.25 x 18 |
The SG generation sharpened the Forester’s edges and dialed up its performance credentials, most famously with the introduction of the 210-horsepower 2.5 XT powered by Subaru’s turbocharged EJ255. Base 2.5 X trims kept the rugged practicality alive, while XT buyers got a genuine sport-utility hot rod well ahead of its time. RBP stocks tire fitments for every SG trim level, including the wider performance-oriented sizes originally equipped on XT models and the taller all-season options that shipped on the 2.5 X. Owners running aftermarket wheels, STI-spec plus-size setups, or modest lift kits will find SG-friendly sizing throughout the RBP catalog.
The SG runs four core rim diameters: 16 inch, 17 inch, and 18 inch. Factory and OE-optional sizing spans 215/60R16 (26.16 x 8.46 x 16), 215/55R17 (26.31 x 8.46 x 17), 225/50R17 (25.86 x 8.86 x 17), 225/55R17 (26.74 x 8.86 x 17), 225/45R18 (25.97 x 8.86 x 18), and 235/45R18 (26.33 x 9.25 x 18). The table below lays out each factory size and its flotation equivalent for the 2002–2008 Subaru Forester SG.
| Diameter | Standard Sizing | Flotation Sizing |
|---|---|---|
| 16 Inch | 215/60R16 | 26.16 x 8.46 x 16 |
| 17 Inch | 215/55R17 | 26.31 x 8.46 x 17 |
| 17 Inch | 225/50R17 | 25.86 x 8.86 x 17 |
| 17 Inch | 225/55R17 | 26.74 x 8.86 x 17 |
| 18 Inch | 225/45R18 | 25.97 x 8.86 x 18 |
| 18 Inch | 235/45R18 | 26.33 x 9.25 x 18 |
The SH marked a major turning point in the Forester lineage. Subaru pivoted from the wagon-like silhouette of the SF and SG to a taller, boxier, more traditionally SUV-shaped body, stretching the wheelbase by nearly four inches and giving rear passengers and cargo the kind of space the previous cars lacked. Trim levels stretched from the 2.5 X base through the 2.5 X Premium, 2.5 X Limited, and the turbocharged 2.5 XT Premium and Touring. RBP offers tires for every SH trim, whether you’re refreshing the original 16-inch steelies on a work-ready X, upgrading the 17-inch Premium alloys, or running a plus-size 18 or 19 on an XT.
The SH generation uses rim diameters of 16 inch, 17 inch, 18 inch, and 19 inch. OE and OE-optional fitments include 215/65R16 (27.00 x 8.46 x 16), 225/55R17 (26.74 x 8.86 x 17), 225/50R18 (26.86 x 8.86 x 18), 245/45R18 (26.68 x 9.65 x 18), and 245/40R19 (26.72 x 9.65 x 19). The table below pairs each SH factory size with its flotation conversion for easier off-road tire shopping.
| Diameter | Standard Sizing | Flotation Sizing |
|---|---|---|
| 16 Inch | 215/65R16 | 27.00 x 8.46 x 16 |
| 17 Inch | 225/55R17 | 26.74 x 8.86 x 17 |
| 18 Inch | 225/50R18 | 26.86 x 8.86 x 18 |
| 18 Inch | 245/45R18 | 26.68 x 9.65 x 18 |
| 19 Inch | 245/40R19 | 26.72 x 9.65 x 19 |
The fourth-generation SJ Forester is the one that cemented the nameplate’s reputation as a volume-seller for Subaru. Sold across long trim ladder spanning the 2.5i base, 2.5i Premium, 2.5i Limited, 2.5i Touring, and the short-lived but beloved 2.0XT Premium and 2.0XT Touring turbocharged models, the SJ delivered best-in-class visibility, class-leading AWD traction, and real cargo utility. Rolling Big Power has tire options dialed in for the full SJ range, from daily-driver replacements for the Premium’s 17-inch alloys to aggressive off-road and all-terrain sizing for owners running lift kits, spacer setups, or plus-sized aftermarket wheels.
SJ Foresters run three primary rim diameters: 17 inch, 18 inch, and 19 inch. Factory and OE-optional sizing includes 225/60R17 (27.63 x 8.86 x 17), 225/55R18 (27.74 x 8.86 x 18), 245/50R18 (27.65 x 9.65 x 18), 235/50R19 (28.25 x 9.25 x 19), and 245/45R19 (27.68 x 9.65 x 19). The table below maps each factory size to its flotation equivalent for the 2012–2022 Subaru Forester SJ.
| Diameter | Standard Sizing | Flotation Sizing |
|---|---|---|
| 17 Inch | 225/60R17 | 27.63 x 8.86 x 17 |
| 18 Inch | 225/55R18 | 27.74 x 8.86 x 18 |
| 18 Inch | 245/50R18 | 27.65 x 9.65 x 18 |
| 19 Inch | 235/50R19 | 28.25 x 9.25 x 19 |
| 19 Inch | 245/45R19 | 27.68 x 9.65 x 19 |
The fifth-generation SK moved the Forester onto Subaru’s stiffer, lighter Global Platform and introduced the now-iconic Wilderness trim, a true factory-built off-roader with added ground clearance, retuned suspension, and more aggressive A/T-ready rubber. Trim levels run deep on this generation: Base, Premium, Sport, Limited, Touring, and Wilderness, each with its own wheel and tire spec. RBP supplies tires for every SK trim and configuration, whether you’re sticking close to OE sizing for a quiet commuter setup or stepping up to an aggressive all-terrain tire to match the Wilderness ethos.
The SK generation uses three rim diameters: 17 inch, 18 inch, and 19 inch. OE and OE-optional sizing covers 225/60R17 (27.63 x 8.86 x 17), 225/55R18 (27.74 x 8.86 x 18), 245/50R18 (27.65 x 9.65 x 18), and 245/45R19 (27.68 x 9.65 x 19). The table below breaks down each SK factory size and its flotation equivalent so you can cross-reference the right RBP tire in seconds.
| Diameter | Standard Sizing | Flotation Sizing |
|---|---|---|
| 17 Inch | 225/60R17 | 27.63 x 8.86 x 17 |
| 18 Inch | 225/55R18 | 27.74 x 8.86 x 18 |
| 18 Inch | 245/50R18 | 27.65 x 9.65 x 18 |
| 19 Inch | 245/45R19 | 27.68 x 9.65 x 19 |
The sixth-generation SL is the most refined Forester ever built, pairing a redesigned body on an evolved Subaru Global Platform with a standard 2.5-liter Boxer and a new 2.5 Hybrid variant co-developed with Toyota. Trim levels carry forward the familiar Base, Premium, Sport, Limited, Touring, and Wilderness hierarchy, now joined by dedicated Hybrid trims that pull their own unique wheel and tire fitments. Rolling Big Power has SL sizing in the catalog from day one, covering everything from OE replacement on a Limited’s 18s to plus-sized 19-inch Hybrid fitments and all-terrain options for the Wilderness crowd.
The SL offers three rim diameters: 17 inch, 18 inch, and 19 inch. Factory and OE-optional sizing includes 225/60R17 (27.63 x 8.86 x 17), 225/55R18 (27.74 x 8.86 x 18), 245/50R18 (27.65 x 9.65 x 18), 235/50R19 (28.25 x 9.25 x 19), and 245/45R19 (27.68 x 9.65 x 19). The table below lists every SL factory size along with its flotation conversion for the 2024–2027 Subaru Forester.
| Diameter | Standard Sizing | Flotation Sizing |
|---|---|---|
| 17 Inch | 225/60R17 | 27.63 x 8.86 x 17 |
| 18 Inch | 225/55R18 | 27.74 x 8.86 x 18 |
| 18 Inch | 245/50R18 | 27.65 x 9.65 x 18 |
| 19 Inch | 235/50R19 | 28.25 x 9.25 x 19 |
| 19 Inch | 245/45R19 | 27.68 x 9.65 x 19 |
The two things that affect tires are time and mileage. Naturally, the compounds on tires have a limited lifespan as they begin to breakdown over time. The mileage on a tire is only a general indication of it’s wear and usage. Neither time nor mileage are accurate indicators of a tire’s usability. The reason for that is because factors such as tire storage and care can improve or diminish lifespan. Typically most tires are manufactured to last at least five years under normal circumstances. If your tires are older than 5 years, it may be a good idea to consider replacements.
Reading the sidewall and understand tire sizing options can seem difficult at first. Once you learn the basics of what these numbers and markings mean, it becomes much simpler. Oftentimes original equipment tires use standard sizing designations, such as 255/70R17. However, when upgrading tires, especially for the Subaru Outback, you may come across flotation sizing designations. These will typically read as 35×12.50×17.
The best tire size is the one that matches your Forester's factory specification or a calculated plus-size that respects the original rolling diameter. Sticking within roughly three percent of the OE diameter keeps your speedometer, odometer, ABS, and AWD control modules calibrated correctly. If you're looking to add visual presence or off-road traction, RBP offers OE-equivalent flotation sizing and plus-fit options for every Forester generation so you can upgrade tread pattern or sidewall aggression without confusing the vehicle's electronics.
Subaru's Symmetrical AWD is sensitive to differences in rolling diameter between axles, so two things matter: all four tires should be the same size, and the size you run should stay close to OE. Dramatically oversized tires without a matching lift or regearing can stress the center differential, viscous coupling, or transfer clutch over time. RBP can help you identify safe plus-size options that protect your drivetrain while delivering the look and performance you want.
A flotation size is expressed as three numbers, for example 27.63 x 8.86 x 17. The first number is the overall tire diameter in inches, the second is the section width in inches, and the third is the rim diameter in inches. It's the same tire as the metric equivalent, just expressed in a format that makes it easier to compare against true off-road and light-truck tires that are almost always marketed in flotation sizing.
Yes. Every Forester generation from the SF through the SL can accept a genuine all-terrain tire in an OE-matched size, and many will clear a modest step up in diameter without any rubbing or fender trimming. Wilderness-trim SK and SL Foresters come from the factory with A/T-ready clearance. RBP's all-terrain lineup is engineered with quieter tread blocks and optimized wear bars so you get off-road capability without the drone and short tread life of traditional mud-terrains.
OEM tires are built to a price point and tuned for the widest possible buyer, which usually means an all-season compound that's decent at everything and exceptional at nothing. RBP tires are purpose-built, so an RBP all-terrain delivers real bite on dirt, gravel, and snow, while an RBP highway-oriented tire focuses on quiet, long-wearing on-pavement performance. You get a tire that actually matches how you drive your Forester, backed by a pricing structure that leaves room in the budget for the other upgrades you've been planning.
