The Perfect Fit for Every Adventure: A Deep Dive into the Thule Force 3 L Cargo Box

The Thule Force 3 L: Premium Safety Features and 16 Cubic Feet of Storage, No Wrench Required

Hey guys, Rack Attack team here, your number one spot for all things rack related.

Today, we're not just looking at a cargo box; we're focusing on the absolute sweet spot in Thule's new line-up: the Thule Force 3 L rooftop cargo box. This is the model that truly delivers the maximum versatility for the vast majority of SUV and crossover owners. If you've been searching for the ideal blend of capacity, aerodynamics, and user-friendly features, this 16 cubic foot model is it.

We’re taking this incredible roof cargo carrier on a road trip through beautiful, sunny Phoenix, Arizona, to put its features to the test. We will be diving into the specs, comparing it directly to its acclaimed predecessor, the Thule Force XT L, and showing you why the Force 3 L is the definitive choice for your next adventure, whether you’re chasing sun in the desert or snow in the mountains.

Capacity and Dimensions: Why the Thule Force 3 L is the "Sweet Spot"

The Thule Force 3 L is not just a cargo box; it is the ultimate expression of balanced rooftop cargo storage. This is the exact model we have mounted on the truck today, and it is the size we find ourselves recommending most often at Rack Attack.

Watch Blake’s Take on Thule Force 3

 

The Ideal Dimensions

The "L" designation stands for "Large," but its design is meticulously tailored to fit vehicles without causing issues with rear hatch clearance or overwhelming the vehicle's profile.

At 76.8 inches long, the Thule Force 3 L is perfectly suited for most mid-sized SUVs (like a Honda CR-V, Toyota RAV4, or Subaru Forester) and many full-sized crossovers. It’s long enough to accommodate skis up to 175 cm covering most adult all-mountain skis and snowboards—without creating excessive overhang on the vehicle. Its 16 cubic feet capacity easily absorbs all the bulky items that choke up your back seat and trunk: camping tents, sleeping bags, strollers, duffel bags, and that extra gear that’s always just a bit too much for the interior. This box is built to carry up to 165 pounds of gear, maximizing your vehicle's utility without compromising your journey.

 

From XT to 3: The Revolutionary Locking Mechanism

Our first stop is beautiful Papago Park, a spot historically significant as part of the Puma and Maricopa Indian Reservation, and now a major recreational hub. Whether you’re stopping here for a quick hike or a full day of recreation, the gear in your roof cargo carrier needs to be instantly accessible and perfectly secure.

The most significant functional upgrade in the new Thule Force 3 line and a crucial point of differentiation from the older Thule Force XT L is the revolutionary locking mechanism, now called SlideLock.

The LockKnob mechanism on the older Thule Force XT combined the key and the locking knob into a single unit. It was functional, but often required two hands and careful attention to ensure full engagement.

The SlideLock system on the Thule Force 3 L is pure genius in design and safety. It achieves three things simultaneously:

1. Intuitive Opening: To open the box, you simply turn the key and use the ergonomic lid lip (which acts as a natural handle) to pull the lid free.
2. Automatic Locking: When you close the lid, the SlideLock system automatically latches and locks the lid in place, unlike older systems that required a separate action to lock the latches.
3. The Ultimate Safety Indicator: The system provides a clear visual and audible confirmation. A loud, reassuring click confirms the box is latched, and you cannot remove the key until all locking points are correctly engaged.

This feature is paramount for safety. You’re packing up, perhaps distracted by kids or pets, and that final check is vital. The fact that the key remains locked in the cylinder until the lid is secured acts as an unmissable safety check, giving you incredible peace of mind when you hit the road. This upgrade alone is reason enough to choose the Thule Force 3 L over the predecessor.

Tool-Free Confidence: The PowerClick System

Next up is the iconic Tempe Town Lake, a massive staple of the city since its construction began in 1996. The bridge views and the constant flow of visitors are a testament to the area’s vitality. A place this busy demands quick, simple, and safe setups, which brings us to the Thule Force 3 L’s mounting system.

The Thule Force 3 L utilizes Thule’s renowned PowerClick quick-mount system. This is a crucial element that elevates the entire Thule Force experience far above many competitors and older boxes like the Thule Cascade.

 

Installation in Seconds

The installation process is simple:

1. Place the box onto your vehicle's crossbars.
2. Open the dual-side lid (a feature on the Thule Force 3 L that is extremely convenient for tight parking spots).
3. Locate the four internal PowerClick knobs.
4. Turn the knobs to tighten the claws around the crossbars.

The Torque-Limited Guarantee

The best part of the PowerClick system and its most important safety feature is that it is torque-limited.

As you turn the knob, the internal mechanism tightens until it reaches the optimal clamping force on your bars, at which point it delivers a distinct, loud, audible CLICK. You will hear four separate clicks, one for each mounting point, providing indisputable proof that your 16 cu ft roof cargo carrier is secured at the exact, perfect tension.

This system virtually eliminates user error. The PowerClick system is intuitive and safe (just listen for the click in video). Furthermore, the Thule Force 3 L is designed to be universally compatible. While we're using Thule WingBars, the PowerClick system fits seamlessly onto all Thule rack systems and most aftermarket and factory-installed crossbars. This versatility ensures that regardless of your vehicle or rack brand, the Force 3 L is an accessible and easy upgrade to your rooftop cargo storage.

Aerodynamics and Performance: Quiet on the Road

Speaking of safety and reliability, our next stop is the world-famous Fountain Hills Park, home to the massive fountain that shoots hundreds of feet into the air. On the drive here, the performance of the Thule Force 3 L on the highway was nothing short of impressive.

Many people hesitate to add a roof cargo carrier because they fear the persistent wind noise and the impact on fuel efficiency. The Thule Force 3 L tackles both concerns head-on.

The AeroSkin Finish

The box features Thule’s signature AeroSkin technology. This is a textured, diamond-patterned, matte black finish. It looks sleek and some people compare it to a carbon fiber appearance, but its function is purely aerodynamic. This texture is specifically designed to disrupt airflow, effectively reducing drag and wind noise compared to older, smooth-shelled boxes.

Streamlined, Low Profile Design

The L size has a perfect balance of height and length. At just 16.8 inches high, it maintains a relatively low profile on your roof. Its revised, wedge-like shape contributes significantly to its quiet performance, ensuring minimal air resistance and eliminating the annoying whistling or droning that plagued some older Thule Force XT models at high speeds. This attention to detail means a more comfortable ride and a less noticeable impact on your gas mileage. You’ll barely notice it’s there, even when packed to its 165 lb capacity.

The Thule Force 3 L in Context: Compared to Thule Force XT L

The Thule Force XT L was a market leader, but the Thule Force 3 L is a superior evolution, making it the clear choice for anyone currently searching for a new roof cargo carrier or looking to upgrade from an older box.

The SlideLock system alone is the decisive difference. It eliminates the security guesswork of the past, offering a level of confidence in the security of your gear that was previously reserved for Thule’s most expensive lines, such as the Thule Motion XT series. When you compare the Thule Force XT L to the new Thule Force 3 L, you are comparing a great box to a superior one that has been rigorously tested in the Thule Test Center for road safety and durability.

Maximizing Your 16 Cubic Feet: The Thule Go Packs

When you invest in a premium Thule cargo box like the Force 3 L, you want to maximize every inch of that 16 cubic feet of space. This is where the Thule Go Pack duffel system becomes indispensable.

The Thule Go Pack system consists of four 75-liter duffel bags specifically designed to fit perfectly inside Thule cargo boxes. For the Thule Force 3 L, using these Go Packs allows you to utilize the internal dimensions of 73.6 in x 28.7 in x 14.4 in with extreme efficiency, packing your gear tightly around the four PowerClick mounting points.

But the real-world convenience of the Go Packs is unparalleled:

• Color-Coded Organization: The bags are color-coded, solving the age-old "whose bag is whose" dilemma, which speeds up packing and unpacking.
• Backpack Conversion: Each Go Pack can be worn like a backpack. Imagine arriving at a campsite or hotel. Instead of juggling loose items, you can sling the Go Packs onto your back, leaving your hands free to manage children, pets, or other gear. This seamless transition from vehicle to destination makes the adventure infinitely easier.

The Thule Force 3 L combined with the Go Packs transforms your rooftop cargo storage from a simple container into a highly organized, mobile, and efficient luggage system. This combination is essential for the "weekend warrior" or the family seeking hassle-free travel.

 

A Reliable Investment: Quality, Durability, and Accessibility

The Thule Force 3 L is built from thermoformed ABS plastic with an acrylic cap and UV package. This material choice provides rugged durability and it is designed to withstand sun, rain, and snow, year after year.

While the Force 3 line is considered the entry point to Thule’s premium boxes, its construction and features are far from entry-level. The quality shines through in its weatherproof construction and its robust SlideLock and PowerClick systems. It’s a tool that is easy to use, easy to live with, and engineered to last. When you look at the price point compared to its direct competitor in features, the Thule Motion 3 L, the Thule Force 3 L stands out as an exceptional value, giving you all the core functionality and safety features for significantly less.

This is not just a seasonal piece of equipment; it’s a year-round accessory built for the active family. Whether you are using the 16 cu ft space for skis up to 175 cm in winter or for bulky camping gear in the summer, the Force 3 L is designed to deliver reliable performance with minimal fuss.

Conclusion: The Thule Force 3 L Enables Your Exploration

After traversing the sights of Papago Park, Tempe Town Lake, and Fountain Hills, the Thule Force 3 L proves why it is the standout choice in the market today. It brings the best features of Thule’s technology down to the most versatile size and an approachable price point.

We’ve seen how the SlideLock system eliminates security doubts, how the PowerClick system makes installation a guaranteed success, and how the AeroSkin finish ensures a quiet and efficient ride. This box is the perfect complement to your vehicle, adding 16 cubic feet of invaluable, secure, and easily accessible space.

If you’re looking to purchase this Thule Force 3 L model or any other top-tier roof cargo carrier, visit us at Rack Attack. With over 40 locations across North America, chances are we have a store right in your backyard. If you prefer to shop from the comfort of your home, you can find the entire line, including great bundles and deals, at Rackattack.com

Get out there, explore your own backyard, and let the Thule Force 3 L carry the load!