Let's dive into the world of the 2013 Jeep Wrangler and explore what it takes to run 37-inch tires. Thinking about beefing up your 2013 Jeep Wrangler with some serious off-road capability? One of the most common upgrades enthusiasts consider is fitting larger tires, specifically 37-inch tires. But before you jump into such a significant modification, it's crucial to understand what's involved. Can your Wrangler handle the change? What modifications are necessary, and what are the potential drawbacks? Let's break it down.

Understanding the Basics

Stock Capabilities of the 2013 Jeep Wrangler

When discussing the feasibility of installing 37-inch tires on a 2013 Jeep Wrangler, it's essential, first and foremost, to understand the vehicle's stock capabilities. The 2013 Jeep Wrangler, right off the assembly line, is designed as a capable off-roader, but it comes with limitations primarily dictated by its factory setup. The standard axles, gearing, suspension, and body clearance are all configured for tires much smaller than 37 inches. Attempting to simply bolt on such large tires without any modifications is not only unsafe but can also lead to significant mechanical problems. Understanding these limitations is key to planning a successful and safe upgrade.

The stock axles, typically Dana 30s or Dana 44s depending on the model, are not designed to handle the increased stress and torque that 37-inch tires exert. The factory gearing will also struggle to turn the larger tires efficiently, leading to a significant loss of power and fuel economy. Furthermore, the stock suspension and body simply do not provide enough clearance to accommodate 37-inch tires without rubbing, which can damage both the tires and the vehicle's body. Therefore, a comprehensive approach is needed, addressing each of these areas to ensure the Wrangler can safely and effectively handle the upgrade. Recognizing the initial constraints allows for a targeted modification plan, ensuring that each upgrade complements the others for optimal performance and reliability. In essence, understanding the starting point is the foundation for a successful transformation.

Why 37-Inch Tires?

So, why do people even consider 37-inch tires for their Wranglers? The allure of 37-inch tires is rooted in the enhanced off-road capabilities they provide. These larger tires offer increased ground clearance, allowing the Wrangler to navigate over larger obstacles and traverse more challenging terrain. This increased clearance can be the difference between getting stuck and successfully overcoming an obstacle on the trail. Moreover, 37-inch tires provide a larger contact patch, which improves traction on various surfaces such as rocks, mud, and sand. This enhanced traction translates to better control and stability in off-road conditions, making the Wrangler a more capable and confident performer.

Beyond the functional benefits, there's also the aesthetic appeal. Let's be honest, a Wrangler equipped with 37-inch tires simply looks more aggressive and imposing. This visual upgrade is often a significant factor for enthusiasts who want to make a statement with their vehicle. However, it's important to remember that the benefits of 37-inch tires come with trade-offs. The increased size and weight of the tires can negatively impact on-road performance, fuel economy, and component wear. Thus, it's crucial to weigh the advantages against the disadvantages and carefully consider whether 37-inch tires are the right choice for your specific needs and driving style. Ultimately, the decision to upgrade to 37-inch tires should be based on a clear understanding of both the performance gains and the required modifications to ensure a safe and reliable setup.

Essential Modifications

Lift Kit

To accommodate 37-inch tires on a 2013 Jeep Wrangler, a lift kit is absolutely essential. Without a lift, the tires would rub against the fenders and other parts of the vehicle, causing damage and limiting mobility. The primary purpose of a lift kit is to raise the body and/or suspension of the Wrangler, creating the necessary clearance for the larger tires. Lift kits come in various sizes, typically ranging from 2.5 inches to 4.5 inches or more. For 37-inch tires, a lift of at least 3.5 to 4 inches is generally recommended to ensure adequate clearance and prevent rubbing during articulation.

There are two main types of lift kits: body lifts and suspension lifts. Body lifts are less expensive and involve raising the body of the vehicle relative to the frame. However, they do not increase ground clearance and can compromise the vehicle's center of gravity. Suspension lifts, on the other hand, involve modifying the suspension components to raise the vehicle. These kits provide increased ground clearance and improved off-road performance. When choosing a lift kit, it's important to consider the quality of the components and the intended use of the vehicle. A high-quality suspension lift kit will typically include new springs, shocks, control arms, and other necessary hardware to ensure proper geometry and handling. In addition, it's crucial to have the lift kit professionally installed to ensure that all components are properly aligned and torqued. A properly installed lift kit will not only provide the necessary clearance for 37-inch tires but also improve the Wrangler's overall off-road capabilities and appearance. Therefore, investing in a quality lift kit and professional installation is a worthwhile investment for anyone considering this upgrade.

Axle Reinforcement or Replacement

One of the most critical modifications when running 37-inch tires on a 2013 Jeep Wrangler involves addressing the axles. The stock Dana 30 or Dana 44 axles, which come standard on most Wranglers, are simply not designed to handle the increased stress and torque exerted by larger tires. The increased weight and rolling resistance of 37-inch tires can lead to axle shaft failure, differential damage, and other costly mechanical problems. Therefore, reinforcing or replacing the axles is a necessary step to ensure the longevity and reliability of the vehicle.

There are several options for addressing the axle issue. One option is to reinforce the existing axles with aftermarket components such as chromoly axle shafts, heavy-duty differential covers, and truss systems. These upgrades can significantly increase the strength and durability of the stock axles, making them better able to withstand the stresses of larger tires. However, even with these upgrades, the stock axles may still be a weak point, especially under heavy off-road use. Another option is to replace the stock axles with stronger aftermarket axles, such as Dana 60s or even larger axles. These axles are designed specifically for off-road use and can handle the stresses of larger tires without issue. While this option is more expensive, it provides the greatest peace of mind and is often the preferred choice for serious off-roaders. Ultimately, the decision of whether to reinforce or replace the axles will depend on the intended use of the vehicle and the budget. However, it's important to recognize that addressing the axle issue is a crucial step in ensuring the reliability of the Wrangler when running 37-inch tires.

Gearing

The factory gearing in a 2013 Jeep Wrangler is optimized for the stock tire size. When you increase the tire size to 37 inches, you effectively change the overall gear ratio, which can have a significant impact on the vehicle's performance. The larger tires require more torque to turn, which can lead to a decrease in acceleration, reduced fuel economy, and increased strain on the engine and transmission. To compensate for this, it's necessary to re-gear the axles to a lower (numerically higher) gear ratio.

Re-gearing involves replacing the pinion and ring gears in the axles with gears that have a different tooth count. This effectively changes the ratio between the engine's RPM and the wheels' RPM, providing more torque to turn the larger tires. The ideal gear ratio will depend on the engine, transmission, and intended use of the vehicle. For 37-inch tires, a gear ratio of 4.56, 4.88, or even 5.13 is often recommended. Re-gearing can significantly improve the Wrangler's performance with 37-inch tires, restoring acceleration, improving fuel economy, and reducing strain on the drivetrain. In addition, it can make the vehicle more enjoyable to drive, both on and off-road. It's important to have the re-gearing performed by a qualified mechanic to ensure that the gears are properly installed and set up. A properly re-geared Wrangler will be much more capable and reliable with 37-inch tires.

Body Modifications and Clearancing

Even with a lift kit, some body modifications and clearancing may be necessary to prevent the 37-inch tires from rubbing against the body of the 2013 Jeep Wrangler. The amount of clearancing required will depend on the specific lift kit, wheel offset, and tire size. Common areas where rubbing can occur include the fenders, fender liners, and rocker panels.

One common modification is to trim the fenders to create more clearance for the tires. This can be done with a cutting wheel or saw, and it's important to be careful not to damage the underlying body panels. Another option is to install aftermarket fenders that are designed to provide more clearance. These fenders are typically made of steel or aluminum and can be painted to match the vehicle's color. In addition to trimming or replacing the fenders, it may also be necessary to trim or remove the fender liners. These liners are made of plastic and can easily be trimmed with a knife or scissors. Finally, some rubbing may occur on the rocker panels, especially during off-road articulation. This can be addressed by installing rocker guards or sliders, which protect the rocker panels and provide a smooth surface for the tires to rub against. Ultimately, the goal of body modifications and clearancing is to ensure that the tires can move freely without rubbing against any part of the vehicle. This will not only prevent damage to the tires and body but also improve the Wrangler's off-road performance.

Considerations and Potential Drawbacks

On-Road Handling and Ride Quality

While 37-inch tires can significantly enhance a 2013 Jeep Wrangler's off-road capabilities, it's essential to consider the potential impact on on-road handling and ride quality. The larger tires can affect the vehicle's steering, braking, and overall stability on paved roads. The increased weight and rolling resistance of the tires can make the steering feel heavier and less responsive. Additionally, the taller tire sidewalls can contribute to body roll during cornering, making the vehicle feel less stable. Braking performance may also be reduced, as the larger tires require more force to stop. To mitigate these effects, it's important to choose high-quality tires that are designed for both on and off-road use. Furthermore, upgrading the steering components, such as the steering box and tie rod ends, can improve the vehicle's steering response and handling. It's also important to adjust the tire pressure to the recommended levels to ensure optimal handling and ride quality. Despite these measures, it's important to recognize that a Wrangler with 37-inch tires will likely not handle as well on the road as a stock Wrangler. Therefore, it's important to carefully consider the trade-offs and decide whether the benefits of the larger tires outweigh the potential drawbacks in terms of on-road performance.

Fuel Economy

One of the most noticeable drawbacks of running 37-inch tires on a 2013 Jeep Wrangler is the decrease in fuel economy. The larger tires require more energy to turn, which puts a greater load on the engine and transmission. This increased load translates to lower fuel economy, often by as much as 2-4 miles per gallon or more. The exact amount of the decrease will depend on the specific tires, gear ratio, and driving style. However, it's safe to say that you can expect to see a significant reduction in fuel economy when upgrading to 37-inch tires. To minimize the impact on fuel economy, it's important to choose lightweight tires and wheels. Furthermore, re-gearing the axles to a lower gear ratio can help to restore some of the lost power and improve fuel economy. However, even with these measures, it's unlikely that you will be able to maintain the same fuel economy as a stock Wrangler. Therefore, it's important to factor in the cost of reduced fuel economy when considering this upgrade. Ultimately, the decision of whether to upgrade to 37-inch tires should be based on a careful assessment of the benefits and drawbacks, including the potential impact on fuel economy.

Wear and Tear on Components

Running 37-inch tires on a 2013 Jeep Wrangler can accelerate wear and tear on various components, including the axles, ball joints, wheel bearings, and brakes. The increased weight and stress of the larger tires put a greater strain on these components, which can lead to premature failure. To mitigate this effect, it's important to use high-quality replacement parts and perform regular maintenance. Upgrading the axles, ball joints, and wheel bearings to heavy-duty versions can help to increase their lifespan. It's also important to check the brakes regularly and replace them as needed. In addition, it's a good idea to inspect the suspension components periodically for wear and tear. By performing regular maintenance and using high-quality parts, you can help to extend the life of the Wrangler's components and minimize the risk of breakdowns. However, it's important to recognize that running 37-inch tires will inevitably lead to increased wear and tear. Therefore, it's important to factor in the cost of increased maintenance and repairs when considering this upgrade.

Conclusion

So, can a 2013 Jeep Wrangler handle 37-inch tires? The answer is a qualified yes. While it's not a simple bolt-on affair, with the right modifications, a 2013 Wrangler can indeed rock 37s. It requires a comprehensive approach, addressing the suspension, axles, gearing, and body. It's not a cheap endeavor, and it does come with trade-offs like reduced fuel economy and increased wear and tear. But for those who crave the ultimate off-road capability and the aggressive look, it can be a worthwhile upgrade.