All About Subaru Forester Springs: Specifications, Performance, and Common Uses

Types of Subaru Forester Springs

Subaru Forester springs come in various types, each engineered to meet specific performance, comfort, and capability requirements. As a critical component of the vehicle’s suspension system, springs play a vital role in ride quality, handling stability, load support, and overall driving experience. While some spring types are standard in modern Foresters, others are used in select models or available as aftermarket upgrades.

Below is a detailed breakdown of the most common types of springs associated with the Subaru Forester, including their function, advantages, and typical applications.

Coil Springs

The primary suspension spring used in all modern Subaru Forester models—both front and rear.

Advantages

• Excellent balance of comfort and control
• Compact design ideal for independent suspension
• Precisely tuned for weight distribution and handling
• Durable and reliable under normal driving conditions

Limitations

• Can sag over time with heavy use
• Limited adjustability in ride height
• Performance variants may require upgrades

Best for: OEM applications, daily driving, all-weather reliability, and balanced on/off-road performance

Air Springs (Aftermarket)

Optional air-assisted or full air suspension systems added via aftermarket kits.

Advantages

• Adjustable ride height for load leveling
• Improved comfort when towing or carrying heavy cargo
• Can enhance off-road clearance dynamically
• Smooth, adaptive ride quality

Limitations

• Higher cost and complexity
• Requires air compressor and control system
• Potential for leaks or electrical issues
• Not factory-standard on any Forester trim

Best for: Towing setups, overlanding builds, adaptive suspension enthusiasts

Performance Coil Springs

Upgraded coil springs designed for enhanced handling and reduced body roll.

Advantages

• Lower center of gravity for better cornering
• Reduced body roll during aggressive maneuvers
• Made from high-tensile steel for longevity
• Compatible with aftermarket shocks and struts

Limitations

• Slightly firmer ride than stock
• May reduce ground clearance if not paired correctly
• Requires professional installation for optimal alignment

Best for: Sport-tuned suspensions, drivers who enjoy spirited driving, and handling-focused modifications

Lifted/Off-Road Springs

Heavy-duty coil springs engineered to increase ground clearance for off-road use.

Advantages

• Increased ride height for rough terrain
• Better approach and departure angles
• Improved articulation and suspension travel
• Supports larger tires and added vehicle weight

Limitations

• May affect OEM ride calibration
• Potential need for alignment and strut extension
• Slightly reduced on-road comfort

Best for: Overlanding, trail driving, winter adventures, and rugged terrain navigation

Other Spring Types (Rare or Not Used in Forester)

While the following spring types are part of automotive suspension history or used in other vehicle categories, they are not typically found in the Subaru Forester lineup:

• Torsion Bars: These are long metal bars that twist to absorb suspension forces. While common in some trucks and older vehicles (like certain Chrysler or Jeep models), torsion bars are not used in the Forester’s independent suspension design. They are more compact but less refined in ride quality compared to coil springs.

• Leaf Springs: Composed of layered steel strips, leaf springs are primarily used in rear axles of trucks and commercial vehicles for heavy load capacity. The Subaru Forester, being a unibody SUV with independent rear suspension, does not use leaf springs. They are outdated for this class of vehicle due to their weight and stiffness.

Expert Tip: When upgrading your Forester's springs, always consider pairing them with compatible shocks or struts. Mismatched components can lead to poor ride quality, premature wear, or unsafe handling. For lifted setups, a full suspension kit often provides better balance and performance than standalone spring replacements.

Features of Subaru Forester Springs: Engineering for Performance and Durability

Subaru Forester coil springs are integral components of the vehicle’s suspension system, designed to deliver a balance of ride comfort, handling precision, and long-term reliability. Engineered for both on-road refinement and off-road resilience, these springs incorporate advanced materials and design principles to meet the demands of diverse driving conditions—from urban commutes to rugged terrain. Below is a detailed breakdown of the key features that define the performance and durability of Subaru Forester springs.

1. High-Strength Material Composition

Subaru Forester springs are constructed from premium-grade steel alloys, typically including chrome silicon or silicon-manganese steel. These materials are selected for their exceptional tensile strength, fatigue resistance, and ability to withstand repeated stress cycles without deformation.

To further enhance longevity, many springs are coated with a zinc-based corrosion-resistant layer, which protects against environmental degradation. This strategic material selection allows the springs to remain lightweight while maintaining structural integrity—ensuring optimal performance even under extreme loads and temperature variations.

2. Superior Rust and Corrosion Resistance

Given the Forester’s reputation for all-weather and all-terrain capability, its suspension components must endure exposure to moisture, road salt, and harsh climates. To combat this, Subaru employs protective measures such as:

• Electro-coated primers applied before final painting
• Spray-on anti-corrosion coatings that seal vulnerable surfaces
• Sealed mounting points to prevent moisture ingress into the spring seat

These features collectively prevent oxidation and pitting, preserving spring elasticity and structural performance over time—especially critical in regions with heavy winter salting or coastal humidity.

3. Precision-Engineered Spring Rates

The spring rate—measured in pounds per inch (lb/in)—determines how much force is required to compress the spring by one inch. Subaru Forester springs are calibrated to deliver an ideal equilibrium between:

Comfort-Oriented Tuning

Lower spring rates allow for greater suspension travel under light loads, absorbing small bumps and road imperfections for a smoother ride. Ideal for daily driving and passenger comfort.

Performance & Load Support

Higher spring rates resist compression under heavy loads or during aggressive cornering, reducing body roll and maintaining tire contact with the road. Essential for towing, off-roading, or carrying cargo.

This balanced tuning ensures the Forester remains stable and responsive across a wide range of driving scenarios.

4. Tapered Coil Design for Enhanced Fit and Function

Many Subaru Forester models utilize tapered (or pigtail) coil springs, where one end of the spring is slightly narrower than the other. This design offers several advantages:

• Improved seating alignment within the upper and lower spring perches
• Reduced spring noise and chatter during compression and rebound
• Better centering of the suspension load, minimizing lateral stress on shock absorbers
• Space efficiency in compact suspension bays, allowing for more compact strut assemblies

The tapered profile also helps prevent spring bind, enhancing both ride quality and component lifespan.

5. Progressive Winding for Adaptive Suspension Response

On select models, Subaru implements progressively wound springs, where the spacing between coils varies along the length of the spring. Typically, the coils are closer together at one end and gradually widen toward the other.

This design enables:

Soft Initial Compression

Under light loads (e.g., normal cruising), only the wider-spaced coils engage, providing a plush, comfortable ride over small bumps and pavement irregularities.

Stiffer Response Under Load

As compression increases (e.g., during cornering, braking, or off-road impact), more coils engage progressively, increasing resistance and preventing bottoming out.

This dual-response behavior makes progressive springs ideal for the Forester’s versatile use case—delivering comfort on highways and resilience on rough trails.

Important: When replacing Subaru Forester springs, always use OEM-spec or high-quality aftermarket parts that match the original spring rate, length, and winding type. Mismatched springs can lead to uneven ride height, poor handling, accelerated wear on shocks and bushings, and compromised safety. Additionally, springs should be replaced in axle pairs (front or rear) to maintain balanced suspension performance.

How to Use Subaru Forester Springs Properly

Proper handling, installation, and maintenance of Subaru Forester springs are crucial for ensuring optimal suspension performance, ride comfort, and long-term vehicle safety. These components play a vital role in supporting the vehicle’s weight, absorbing road shocks, and maintaining stability during driving. Following best practices helps maximize spring lifespan and ensures your vehicle handles predictably under all conditions.

Professional Installation Recommended

While experienced DIY mechanics may attempt spring replacement, this task involves significant safety risks and technical precision. Coil springs store high levels of mechanical energy and require specialized tools such as spring compressors and torque wrenches for safe handling.

• Improper installation can lead to misalignment, uneven ride height, or catastrophic spring failure
• Professional technicians use calibrated equipment to ensure correct mounting position and suspension geometry
• Post-installation wheel alignment is essential to prevent premature tire wear and handling issues

Safety first: Always disconnect the battery and secure the vehicle on level ground before beginning work

Regular Inspections for Wear and Damage

Incorporate spring inspections into routine maintenance—especially every 15,000 miles or when servicing shocks or struts. Early detection of damage prevents more costly repairs and enhances driving safety.

• Look for visible cracks, especially near the end coils where stress concentration is highest
• Check for excessive rust or corrosion that compromises structural integrity
• Observe sagging or reduced ride height, which indicates spring fatigue
• Inspect rubber isolators and seat mounts for dry rot or deformation

Pro tip: Inspect springs more frequently if used for towing, off-roading, or commercial purposes

Respect Weight Limits and Load Distribution

Subaru Forester springs are engineered to support specific load capacities defined by the manufacturer. Exceeding these limits—even temporarily—can cause permanent deformation or accelerated fatigue.

• Refer to the vehicle’s owner manual or door jamb label for Gross Vehicle Weight Rating (GVWR)
• Avoid rooftop cargo boxes or heavy rear loads that unbalance the suspension
• Distribute weight evenly across the cargo area to prevent uneven spring compression
• Consider auxiliary support (like air helper springs) for frequent heavy hauling

Critical note: Overloading not only damages springs but also affects braking, steering, and fuel efficiency

Avoid Harsh Impacts and Rough Terrain

Sudden impacts from potholes, curbs, or uneven off-road trails place extreme stress on suspension components. Repeated exposure shortens spring life and may lead to coil breakage.

• Reduce speed when approaching bumps, dips, or uneven surfaces
• Use caution when driving over speed humps—approach at an angle if necessary
• Be mindful of low-clearance obstacles that could bottom out the suspension
• After off-road use, inspect springs for dents, scrapes, or misalignment

Longevity tip: Smooth driving habits significantly extend the service life of suspension components

Replace Springs in Pairs

When one spring shows signs of wear or failure, it's strongly recommended to replace both springs on the same axle—even if the other appears intact. This maintains balanced suspension behavior and prevents handling imbalances.

• Replacing only one spring can cause the vehicle to lean or pull to one side
• Mismatched spring rates affect cornering stability and ride quality
• Pair replacement ensures even ride height and predictable steering response
• For high-mileage vehicles, consider replacing all four springs simultaneously

Best practice: Always replace front or rear springs as a set for optimal performance

Use Quality Replacement Parts

Not all aftermarket springs are created equal. Choosing OEM-spec or premium-grade replacements ensures compatibility, durability, and performance consistency.

• OEM or OE-equivalent springs match factory ride height and tuning characteristics
• Premium brands often include corrosion-resistant coatings and enhanced metallurgy
• Avoid ultra-low-cost springs with inconsistent winding or poor heat treatment
• Look for certifications like ISO 9001 or TÜV for quality assurance

Expert advice: Pair new springs with fresh shocks or struts for a complete suspension refresh

Professional Recommendation: For most Subaru Forester owners, combining professional installation with periodic inspections and responsible driving habits offers the best balance of safety, comfort, and cost-effectiveness. If upgrading for performance or load-carrying needs, consult a suspension specialist to select the right spring rate and design for your specific application.

Additional Best Practices

• Break-in Period: After installation, avoid aggressive driving for the first 200 miles to allow components to settle
• Corrosion Protection: In snowy or coastal regions, wash undercarriage regularly to prevent salt buildup
• Alignment Check: Always perform a four-wheel alignment after spring replacement
• Noise Monitoring: Squeaking or clunking noises may indicate worn spring seats or isolators
• Documentation: Keep service records to track spring age and replacement history

How to Choose the Right Subaru Forester Springs

Selecting the appropriate springs for your Subaru Forester is a crucial decision that directly impacts ride comfort, handling performance, off-road capability, and long-term durability. Whether you're maintaining factory specifications or modifying your vehicle for enhanced performance, understanding the key factors in spring selection ensures optimal results. Below is a comprehensive breakdown of the most important considerations when choosing springs for your Forester.

Important Note: Incorrect spring selection can lead to poor ride quality, accelerated wear on suspension components, compromised safety, and reduced vehicle stability. Always verify compatibility and consult with a qualified suspension specialist if unsure.

Key Factors in Spring Selection

• Driving Needs and Usage Patterns

  Your typical driving environment and vehicle usage should be the primary guide in selecting springs. For drivers who primarily use their Forester for daily commuting, highway travel, or family transportation, OEM or OEM-replacement springs offer the best balance of comfort, noise reduction, and predictable handling.

  If you frequently drive on rough terrain, engage in off-roading, carry heavy loads, or tow trailers, consider heavy-duty or performance-oriented springs. These provide increased ground clearance, better articulation, improved load support, and resistance to bottoming out. Lift kits often include upgraded springs designed specifically for enhanced off-road capability while maintaining on-road drivability.

• Type of Spring Construction

  Subaru Foresters typically come equipped with coil springs, which are engineered for a balance of comfort and control. Many factory springs feature progressive winding—where the coils are closer together at one end—allowing for a softer initial compression under light loads and firmer resistance during aggressive cornering or over bumps.

  Aftermarket options include linear-rate coils (consistent stiffness throughout compression) and advanced progressive designs that offer more tailored response. Some performance springs use tapered or variable-pitch designs to optimize space efficiency and dynamic response. While performance springs enhance cornering stability and reduce body roll, they often result in a stiffer ride, particularly on uneven pavement.

• Spring Rate (Measured in lbs/in)

  The spring rate determines how much force is required to compress the spring by one inch. This is one of the most critical specifications when selecting replacement or upgrade springs. A higher spring rate (e.g., 200+ lbs/in) provides greater resistance to compression, making it ideal for:

  • Heavy cargo or passenger loads
  • Towing applications
  • Performance driving with reduced body roll
  • Off-road use requiring resistance to bottoming out

  Conversely, lower spring rates (e.g., 150–180 lbs/in) deliver a softer, more compliant ride—perfect for city driving, comfort-focused setups, or vehicles with minimal added weight. However, they may sag under load or allow excessive body lean during spirited driving.

• Cost and Budget Considerations

  Spring pricing varies significantly based on quality, design, and brand. OEM Subaru springs ensure perfect fitment and factory-calibrated performance but may come at a premium price. Aftermarket options range from budget-friendly replacements to high-end performance springs from reputable brands like Bilstein, Eibach, or TEIN.

  While cost is a valid concern, investing in high-quality springs often pays off through improved longevity, better ride characteristics, and reduced stress on other suspension components such as shocks, bushings, and struts. Avoid extremely low-cost springs made from inferior materials, as they may fatigue prematurely or fail under stress.

• Model-Year Compatibility and Fitment

  Subaru has made several updates to the Forester’s suspension system across generations (e.g., 2014–2018 vs. 2019–present). Springs are not always interchangeable between model years due to changes in mounting points, strut design, or ride height specifications.

  Always confirm that the springs you select are explicitly rated for your Forester’s exact model year, trim level, and engine configuration. For example, the Wilderness trim often comes with unique suspension tuning that may require specific spring rates. When in doubt, consult a professional mechanic or use fitment tools provided by reputable auto parts retailers.

Expert Tip: When replacing springs, it's highly recommended to replace them in pairs (front or rear axle) or as a full set. Mixing old and new springs can create imbalanced suspension behavior, leading to uneven handling, premature tire wear, and potential safety issues. Additionally, consider having your alignment checked after spring installation.

Final Recommendations

• Test your current setup: Note any sagging, bottoming out, or excessive body roll before selecting new springs.
• Match springs to your shocks/struts: Upgraded springs work best when paired with compatible dampers for balanced performance.
• Check local regulations: Some lift kits may not comply with regional vehicle height laws.
• Document your changes: Keep records of spring type, rate, and installation date for future maintenance or resale.
• Consult forums and reviews: Real-world feedback from other Forester owners can provide valuable insights into brand reliability and performance.

Choosing the right springs for your Subaru Forester is more than just a mechanical decision—it's about aligning your vehicle’s performance with your lifestyle. By carefully evaluating your driving needs, understanding technical specifications, and prioritizing quality and compatibility, you can enhance both the capability and comfort of your Forester for years to come.

Frequently Asked Questions About Subaru Suspension Springs

Subaru suspension springs play a critical role in the overall performance, comfort, and safety of your vehicle. Their primary functions include:

• Support Vehicle Weight: Springs bear the load of the vehicle, passengers, and cargo, ensuring the chassis remains at the proper ride height under various conditions.
• Absorb Road Impacts: They cushion the vehicle from bumps, potholes, and uneven terrain, reducing shock transfer to the cabin and improving ride comfort.
• Maintain Stability: By working in tandem with shock absorbers, springs help maintain tire contact with the road, enhancing traction and control during cornering, braking, and acceleration.
• Preserve Vehicle Geometry: Properly functioning springs help maintain the intended alignment and suspension geometry, which is especially important for all-wheel-drive Subarus that rely on balanced weight distribution.

Whether driving on city streets or rugged backroads, the springs are essential for preserving both driving dynamics and long-term component health.

Aftermarket springs can be an excellent upgrade for Subaru Forester owners, depending on their driving needs and goals. Here’s what to consider:

• Performance Enhancement: High-quality aftermarket springs (such as performance or sport-tuned variants) can improve handling, reduce body roll, and offer a more responsive driving experience.
• Ride Height Adjustment: Lifted springs are popular for off-road enthusiasts who need additional ground clearance, while lowering springs appeal to those seeking a sleeker, sportier look.
• Load Capacity: Heavy-duty or progressive-rate springs can better support frequent hauling or roof cargo, maintaining ride quality under load.
• Compatibility & Balance: It's crucial to choose springs designed specifically for the Subaru Forester and to consider matching them with appropriate shocks or a full coilover system for optimal performance.
• Warranty & Reliability: Reputable brands often offer warranties and undergo rigorous testing, but improper installation or low-quality parts can lead to premature wear or safety issues.

In short, aftermarket springs are a smart investment when selected thoughtfully and installed correctly—ideally paired with a professional alignment afterward.

Yes, it is strongly recommended—and often essential—to replace suspension springs in pairs on the same axle (front or rear). Here’s why:

• Balanced Suspension: Using mismatched springs (one new, one old) can create an uneven ride height, leading to poor weight distribution and compromised handling.
• Improved Safety: Balanced springs ensure even tire wear, predictable steering response, and consistent braking performance.
• Prevent Premature Wear: An imbalanced suspension system can place additional stress on shocks, control arms, bushings, and CV joints, leading to faster deterioration of other components.
• Factory Recommendations: Subaru and most automotive experts advise replacing springs in pairs (or as a full set) to maintain the integrity of the suspension system.

Even if only one spring appears damaged, replacing both ensures long-term reliability and performance harmony across the axle.

While suspension springs don’t require regular replacement like brake pads, they should be inspected periodically—especially under demanding conditions. Recommended inspection intervals include:

• Every 15,000–20,000 Miles: During routine maintenance or tire rotations, have a technician visually check for signs of wear or damage.
• After Off-Road Use: Aggressive terrain, deep potholes, or curb strikes can weaken or deform springs over time.
• When Carrying Heavy Loads: Frequent towing or roof cargo can accelerate metal fatigue, so extra checks are wise.
• If Symptoms Arise: Sagging ride height, uneven tire wear, clunking noises over bumps, or reduced ride comfort are red flags that warrant immediate inspection.

Regular inspections help detect issues early, preventing costly damage to related suspension components and maintaining optimal driving safety.

Extending the lifespan of your Subaru’s suspension springs involves a combination of mindful driving habits and proactive maintenance. Key strategies include:

• Avoid Severe Impacts: Steer clear of potholes, speed bumps, and curbs at high speed—sharp jolts can cause immediate damage or cumulative stress.
• Prevent Overloading: Stay within the vehicle’s Gross Vehicle Weight Rating (GVWR). Exceeding load limits puts excessive strain on springs, leading to sagging or breakage.
• Regular Inspections: Check for cracks, corrosion, or sagging during oil changes or seasonal maintenance.
• Pair with Healthy Shocks: Worn shock absorbers increase the workload on springs. Replacing shocks when needed helps preserve spring integrity.
• Drive Smoothly: Gradual acceleration and braking reduce dynamic stress on the suspension system over time.

By following these best practices, Subaru owners can significantly prolong the service life of their suspension springs, ensuring continued comfort, safety, and performance for years to come.