Beginner's Guide to Modding Your 2015+ Subaru Forester: Best Entry-Level Upgrades

Why the 2015+ Forester Is a Great Platform for Modding

The 2015+ Subaru Forester represents a sweet spot for owners who want a vehicle that handles daily duties with ease but also welcomes meaningful upgrades. Whether you're driving the SJ chassis (2015-2018) or the newer SK platform (2019+), you're working with a proven Subaru foundation built on symmetrical all-wheel drive, a boxer engine, and a surprisingly capable suspension geometry.

Understanding the Generations

The SJ Forester (2015-2018) came in two main flavors: the naturally aspirated 2.5i with 170 horsepower, and the turbocharged 2.0XT producing 250 horsepower. The XT variant shares its FA20DIT engine with the WRX, which opens the door to a broader range of performance modifications. Unfortunately, Subaru discontinued the XT after 2018, so if you're shopping for turbo power, this is the generation to find.

The SK Forester (2019+) moved to Subaru's Global Platform (SGP), which improved rigidity, handling, and safety. However, this generation is exclusively powered by the 2.5-liter naturally aspirated FB25 engine. While it's not a power monster, the SK chassis responds well to suspension, exhaust, and exterior upgrades that enhance the driving experience without chasing big horsepower numbers.

Setting Realistic Expectations

If you're coming from the WRX or STI world expecting massive power gains from bolt-ons, the Forester 2.5i will require a mindset shift. This platform shines when you focus on improving capability, comfort, and aesthetics rather than chasing dyno numbers. Think lift kits for trail clearance, exhaust upgrades for a better sound, and protective accessories that let you use the Forester the way it was meant to be used.

For XT owners (2015-2018), there's more room to play with intake, exhaust, and tuning combinations—but even then, the Forester XT is best appreciated as a practical turbocharged crossover rather than a track weapon.

Why Modify at All?

Stock Foresters are great, but they're built to satisfy the widest possible audience. Modifications let you tailor the vehicle to your specific needs. Maybe that means a throatier exhaust note on your morning commute, a 2-inch lift for forest service roads, or LED fog lights for better visibility in winter conditions. The aftermarket for 2015+ Foresters has matured significantly, meaning quality parts are available from trusted manufacturers—many of which you'll find right here at SubiMods.

Exhaust Upgrades: Sound and Flow Without Going Overboard

One of the most popular first modifications for any Subaru owner is an exhaust upgrade, and the 2015+ Forester is no exception. A well-chosen exhaust system transforms the driving experience by adding a more engaging sound character while potentially improving exhaust flow. For Forester owners, the key is finding the right balance—enough presence to enjoy without droning on long highway trips.

Axle-Back vs. Cat-Back: What's the Difference?

Before shopping, it's important to understand your two main options:

• Axle-back systems replace only the rear section of the exhaust, from the rear axle to the exhaust tips. These are typically more affordable, easier to install, and provide a moderate sound improvement without dramatically altering exhaust flow.
• Cat-back systems replace everything from the catalytic converter back, including the mid-pipe, resonator (if applicable), and muffler section. Cat-backs offer greater sound and flow improvements but come at a higher price point and require more involved installation.

For most 2.5i Forester owners, an axle-back system is the ideal starting point. Since the naturally aspirated engine doesn't produce enough power to benefit significantly from improved exhaust flow, the primary goal is sound enhancement—and an axle-back delivers exactly that without breaking the bank.

What to Expect: 2.5i vs. XT

The 2.5i Forester has a naturally aspirated boxer engine that produces a distinctive but subdued tone from the factory. An aftermarket exhaust will deepen and enrich that boxer rumble, making the car feel more alive during acceleration. Don't expect dramatic horsepower gains—maybe 3-5 HP at best—but the improvement in sound quality and throttle response feel is immediately noticeable.

The Forester XT (2015-2018) benefits more substantially from exhaust upgrades due to its turbocharged FA20DIT engine. A cat-back or turbo-back exhaust on the XT can yield 10-20+ horsepower gains when paired with an intake and proper tune. The turbo also muffles some of the classic boxer rumble, so XT owners often pursue exhaust upgrades to reclaim that signature Subaru sound while unlocking additional performance.

Choosing the Right Sound Level

Exhaust systems vary significantly in volume and tone. Here's a general guide:

For a Forester that sees daily duty, commuting, and family use, we generally recommend starting with a mild to moderate exhaust. You can always go louder later, but you can't easily quiet down an overly aggressive system.

Recommended Exhaust Brands

Several reputable manufacturers produce quality exhaust systems for the 2015+ Forester platform. Look for options from brands like Nameless Performance, Invidia, and HKS—all known for their fitment quality, materials, and tuned sound profiles. When shopping, pay close attention to whether the system is resonated (quieter) or non-resonated (louder), and always verify fitment for your specific model year and engine configuration.

Suspension & Lift Kits: Unlocking Off-Road Capability

While WRX and STI owners typically lower their cars for improved handling, Forester owners tend to go the opposite direction—and for good reason. A modest lift transforms your Forester from a capable crossover into a legitimate trail machine, improving ground clearance for forest roads, rocky terrain, and snowy conditions. It's one of the most impactful modifications you can make to this platform.

Why Forester Owners Lift

The stock Forester offers respectable ground clearance (approximately 8.7 inches depending on the model year), but it doesn't take much to find the limits on rougher terrain. A 1.5 to 2-inch lift provides meaningful benefits without dramatically altering the vehicle's on-road manners:

• Increased ground clearance for rocks, ruts, and uneven surfaces
• Room for larger tires (up to 245/65R17 or similar) for improved off-road traction
• Better approach and departure angles to tackle steeper obstacles
• Improved visibility both on and off the road
• Aggressive stance that sets your Forester apart from stock examples

The sweet spot for most Forester builds is a 2-inch lift. This height provides noticeable capability gains while keeping the center of gravity reasonable and avoiding excessive stress on CV axles and other drivetrain components.

Types of Lift Kits

Not all lift kits are created equal. Here's what you'll encounter when shopping:

For budget-conscious builds, spacer lift kits from reputable manufacturers offer excellent value. They're straightforward to install (many owners complete the job in a weekend) and provide the clearance gains most owners are looking for. If you want improved ride quality and damping in addition to lift, consider investing in a full strut and spring package.

Supporting Modifications

Lifting your Forester changes suspension geometry, which can affect handling, tire wear, and component longevity. Depending on your lift height, consider these supporting mods:

• Rear trailing arm spacers: Correct the rear suspension geometry to reduce lateral thrust and tire wear
• Adjustable endlinks: Prevent sway bar preload and binding after lifting
• Alignment: A professional alignment is essential after any lift to ensure proper tire wear and handling
• Camber bolts: Allow for finer alignment adjustments that may not be possible with stock hardware

Recommended Lift Kit Brands

The Forester aftermarket has grown significantly, and several manufacturers now offer well-engineered lift solutions specifically for the 2015+ platform. Look for kits from trusted names like LP Aventure and Rallitek—both known for quality materials, precise fitment, and comprehensive instructions. These brands also offer supporting components like skid plates and bumper guards that complement a lifted build.

Tire Considerations After Lifting

One of the main benefits of lifting is the ability to run larger, more aggressive tires. After a 2-inch lift, most Forester owners can fit tires in the 225/65R17 to 245/65R17 range without rubbing issues. All-terrain tires from brands like BFGoodrich, Falken, and Yokohama are popular choices that balance off-road grip with acceptable on-road manners and noise levels.

Exterior Protection & Lighting: Function Meets Style

If you're planning to actually use your Forester's off-road capability—or simply want to protect it from the hazards of daily driving—exterior protection and lighting upgrades are essential. These modifications serve a dual purpose: they shield your vehicle from damage while giving it a rugged, adventure-ready appearance that sets it apart from stock examples in the parking lot.

Mudflaps: Your First Line of Defense

Mudflaps are one of the most cost-effective modifications you can make to any Subaru, and they're especially valuable on a Forester that sees dirt roads, gravel, or winter conditions. Stock Foresters come with minimal (or no) mud protection, leaving your paint, rocker panels, and the vehicles behind you vulnerable to rock chips and debris.

Quality aftermarket mudflaps offer several advantages:

• Paint protection: Deflect rocks, mud, and road debris away from vulnerable body panels
• Reduced cleanup: Keep dirt and grime contained rather than coating your doors and quarter panels
• Courtesy to others: Minimize the rocks and spray you kick up onto vehicles behind you
• Durability: Aftermarket options are typically thicker and more resilient than OEM alternatives

Rally Armor is the gold standard for Subaru mudflaps, offering urethane construction that's flexible enough to handle impacts without cracking. Their flaps are available in various colors and logo options, allowing you to personalize your Forester's look while adding genuine protection. Installation is straightforward and typically requires no drilling on newer mounting designs.

Skid Plates and Underbody Protection

Once you start venturing off the pavement, your Forester's underside becomes exposed to rocks, roots, and debris that can damage critical components. Factory underbody protection is minimal at best—usually thin plastic covers designed more for aerodynamics than impact resistance.

Aftermarket skid plates protect vulnerable areas including:

• Engine/oil pan: The most critical area to protect from rock strikes
• Transmission: Shields the transmission housing and related components
• Fuel tank: Prevents punctures on rough terrain
• Differential: Protects the rear differential on more aggressive builds

Skid plates are typically constructed from aluminum or steel. Aluminum plates offer a good balance of protection and weight savings, while steel plates provide maximum durability for serious off-road use at the cost of added weight. Brands like LP Aventure and Primitive Racing offer comprehensive skid plate systems designed specifically for the Forester platform.

Bumper Guards and Bull Bars

For Forester owners who want additional front-end protection and mounting options for accessories, bumper guards and bull bars are worth considering. These accessories provide:

• Impact protection: Shield the front bumper and grille from brush, branches, and minor impacts
• Light mounting: Provide mounting points for auxiliary lights and light bars
• Recovery points: Some designs include integrated recovery shackle mounts
• Aggressive aesthetics: Complete the rugged, adventure-ready look

When shopping for bumper protection, ensure the product is designed specifically for your Forester's model year to guarantee proper fitment and avoid interference with sensors, cameras, or airbag systems.

Lighting Upgrades: See and Be Seen

Factory Forester lighting is adequate for normal driving conditions, but it leaves room for improvement—especially if you're driving on unlit back roads or trails after dark. Lighting upgrades range from simple bulb swaps to comprehensive auxiliary light setups.

LED Bulb Upgrades

The easiest lighting upgrade is replacing factory halogen bulbs with modern LED alternatives. LED bulbs offer several advantages:

• Increased brightness: Better illumination of the road ahead
• Whiter light color: More natural daylight-like appearance (typically 5500-6500K)
• Longer lifespan: LEDs last significantly longer than halogen bulbs
• Lower power consumption: Reduced load on your electrical system

Morimoto produces some of the highest-quality LED bulbs on the market, including their popular 2Stroke series. These bulbs feature precision-engineered emitter placement that replicates the halogen filament position, resulting in proper beam patterns without excessive glare to oncoming traffic. The Morimoto 2Stroke 4.0 LED Bulb Kit is an excellent upgrade for fog light applications.

Auxiliary Lighting

For serious off-road capability, auxiliary lights mounted on a bull bar, roof rack, or ditch light brackets provide illumination far beyond what factory headlights can achieve. Options include:

• Light bars: Wide flood patterns for broad area illumination
• Pod lights: Compact, versatile lights for spot or flood applications
• Ditch lights: Mounted at the base of the A-pillar for improved peripheral visibility

When adding auxiliary lights, invest in a proper wiring harness with a relay and switch to ensure safe, reliable operation. Many Forester owners mount the switch in a convenient location on the dash or center console for easy access.

Putting It All Together

The beauty of exterior protection and lighting upgrades is that they work together as a cohesive system. A typical progression might look like this:

1. Start with mudflaps for immediate paint protection
2. Add a front skid plate once you begin exploring unpaved roads
3. Upgrade to LED fog lights for better visibility in adverse conditions
4. Install a bumper guard if you want light mounting options and additional protection
5. Add auxiliary lighting for serious off-road or backcountry use

Each piece builds on the last, creating a Forester that's genuinely prepared for adventure rather than just looking the part.

Conclusion: Building Your Forester One Step at a Time

The 2015+ Subaru Forester is one of the most versatile platforms in the Subaru lineup, equally at home on the daily commute as it is on a remote forest road. Whether you're chasing better breathing with an intake upgrade, adding character with an exhaust system, unlocking off-road capability with a lift kit, or protecting your investment with mudflaps and skid plates—there's no shortage of ways to make your Forester truly yours.

The key to a successful Forester build is intentionality. Unlike some platforms where the goal is simply "more power," Forester modifications tend to be purpose-driven:

• Weekend adventurers prioritize lift kits, all-terrain tires, and underbody protection
• Daily drivers focus on quality-of-life improvements like intakes, exhaust sound, and lighting
• Overlanders build comprehensive setups with protection, recovery points, and auxiliary lighting
• XT owners can pursue meaningful power gains with intake, exhaust, and proper tuning

No matter which direction you take your build, remember these guiding principles:

1. Start with protection. Mudflaps and paint protection cost little but save you from expensive repairs down the road.
2. Build progressively. Each modification should complement the last. A lift kit makes larger tires possible; larger tires make skid plates more important.
3. Buy quality once. The Forester aftermarket has matured significantly, and reputable brands offer parts that fit correctly and last. Cheap alternatives often lead to frustration and replacement costs.
4. Know your limits. For complex installations like lift kits or electrical work, don't hesitate to seek professional help if you're unsure.
5. Tune when required. If you own a Forester XT and pursue power modifications, proper ECU calibration isn't optional—it's essential for reliability.

The Subaru community is one of the most passionate and supportive in the automotive world. Whether you're posting your build progress online, meeting up at a local Subaru event, or waving to a fellow Forester owner on the trail, you're part of something bigger. Your modifications aren't just about making your car better—they're about making it yours.

Ready to start your Forester build? Browse our complete selection of Forester parts and accessories to find everything you need to transform your crossover into the adventure vehicle it was meant to be. And if you have questions along the way, our team is here to help you build it right.