Anyone who has ever packed for a family road trip or a big adventure knows the struggle: how do you fit everything? My car often felt like a sardine can, with luggage encroaching on passenger space, blocking the rear view, and forcing tough decisions about what gear had to be left behind. It was clear I needed a solution to expand my vehicle’s carrying capacity, something beyond just stuffing things into every corner. A good rooftop cargo box seemed like the most practical answer. Without one, every trip was a compromise, sacrificing comfort and sometimes even safety due to obstructed views or overloaded interiors.
- A versatile roof-mounted cargo box for everyday use
- Provides 18 cubic feet of additional packing space
- Designed to fit a wide range a vehciles with maximum space efficiency
Key Considerations Before Choosing a Rooftop Storage Solution
Seeking a rooftop carrier is usually driven by a simple need: more space for travel, sports, or outdoor gear. These accessories effectively move bulky items from inside your vehicle to the roof, freeing up interior space for passengers and improving visibility. The ideal buyer for a cargo box is someone who frequently takes trips requiring extra luggage – families heading on vacation, skiers/snowboarders, campers, or anyone with hobbies involving bulky equipment.
However, rooftop boxes aren’t for everyone. If you rarely travel with much gear, have ample space inside your vehicle, or have severe limitations on where you can store a large, flat object when not in use, this might not be the right path. Someone who just needs occasional extra space might consider a softer, foldable cargo bag, though they lack the security and rigidity of a hard shell box.
Before committing to a purchase, potential buyers should consider several factors: the required volume (measured in cubic feet), compatibility with their vehicle’s roof rack system (crossbar type and spacing), the box’s external dimensions (especially length to ensure rear hatch clearance), the maximum weight capacity, how easy it is to install and remove, whether it opens from one or both sides, its aerodynamic properties (affecting noise and fuel economy), the security features, and critically, how you plan to store the box when it’s not on your car.
- 18 cubic foot (510 L) internal cargo capacity
- Functional rooftop cargo box provides 16 cubic feet of additional packing space
- Secure & protect your gear in this 18 cubic ft. HDPE plastic hard shell vehicle cargo carrier; high-capacity interior dimensions 57 L x 38 1/2 W x 17 3/4 H inches; aerodynamic design for fuel...
Introducing the Thule Force XT Rooftop Cargo Box
The Thule Force XT Rooftop Cargo Box is designed as a versatile solution for adding significant storage space to your vehicle’s roof. Promising secure, easy-to-use, and aerodynamic performance, it aims to solve the perennial problem of overflowing cars on road trips. Specifically, the X-Large size boasts 16 cubic feet of capacity, engineered to fit a wide range of vehicles while minimizing contact with the rear hatch. When you buy it, you get the cargo box itself, the necessary mounting hardware, and tie-down straps for securing your contents.
Compared to some budget options on the market, the Thule Force XT generally offers a more refined mounting system and better build quality, aligning with Thule’s reputation in the outdoor gear world. While perhaps not as heavy-duty as some older, double-walled carriers or Thule’s premium Motion XT line, it hits a sweet spot for many users. The XL size sits in the middle-to-larger end of the Force XT line (Sport, L, XL, XXL), offering a substantial 16 cu ft capacity, a 165 lb load limit, and space for skis/boards up to 175 cm, balanced against external dimensions of 74.75″L x 33″W x 18″H.
This particular Thule box is best for families, campers, or anyone needing ample, secure storage for regular travel, especially those who value easy installation and access. It might not be the best choice if your primary concern is finding the absolute cheapest option, if you only need minimal extra space, or if you specifically require a box that can be easily stored standing upright or mounted on a wall.
Here’s a quick look at the pros and cons:
Pros:
* Significant 16 cubic feet of storage in the XL size.
* Extremely easy and secure installation with the PowerClick quick-mount system.
* Convenient dual-side opening for flexible access.
* Relatively quiet operation on the highway compared to soft carriers.
* Allows for full rear trunk access on many vehicles due to its design.
* Water resistant and keeps contents dry in rain.
Cons:
* Cannot be safely stored vertically according to the manufacturer, requiring significant floor space.
* The top shell plastic feels thin compared to older, more robust designs.
* The LockKnob system can feel slightly flimsy when the box is packed full, and the key can be finicky.
* Adds noticeable wind drag and reduces fuel economy (as expected).
* Requires two people to lift onto the vehicle roof initially.
Diving Deeper: Features and How They Perform
Having used the Thule Force XT X-Large extensively over the past couple of years, including multiple long-haul road trips, I’ve gotten a real feel for how its features translate into real-world usability.
Ample Storage Capacity (16 cu ft)
Let’s talk about the headline feature for most buyers: space. The 16 cubic feet offered by the Thule Force XT XL is substantial. It’s hard to visualize cubic feet, but imagine being able to pack multiple large duffel bags, camping gear like tents and sleeping bags, several folding chairs, beach umbrellas, and still have room left over for jackets or other bulky items. I’ve fit everything from several large suitcases and a cooler to bulky sports equipment like ski boots and helmets. On one memorable trip with my family, I managed to get all our camping gear and clothing for four people into the box, leaving the entire trunk free for groceries and incidentals. This completely transformed the interior comfort of the car – no more bags piled high blocking the rear view, and passengers had legroom instead of luggage-room. It genuinely solves the problem of not having enough space, making longer trips far more relaxed.
PowerClick Quick-Mount System
This feature is, in my opinion, one of the standout aspects of the Force XT. After getting the box onto the roof rack (which, full disclosure, is definitely a two-person job due to its size, even though it’s relatively light), securing it is incredibly easy. You simply position the box, open the lid, and turn the knobs inside. The PowerClick system uses internal clamps that grip your crossbars. As you tighten the knob, the clamp closes, and a torque indicator built into the knob clicks when you’ve reached the optimal tightness. This click is genius – it eliminates guesswork and gives you confidence that the box is securely mounted to your vehicle. You don’t need tools, and the whole process takes just a few minutes. The clamps also have a slight range of movement within tracks, allowing some flexibility for different crossbar spreads, which is a nice touch. While some online reviewers mentioned small plastic clips that help hold the clamps to the box during mounting feel a bit cheap, in my experience, once the clamps are tightened down with the PowerClick system, everything is rock solid. The convenience and security of this system easily justifies opting for a higher-quality Thule box over simpler mounting methods.
Dual-Side Opening
Another seemingly small feature that makes a big difference in usability is the dual-side opening. The Thule Force XT can be opened from either the driver’s side or the passenger’s side. This is incredibly practical, especially when you’re parked in tight spots or just want quick access to something inside without having to walk around the vehicle. You simply unlock and lift the lid from the side that’s most convenient. Need to grab a jacket or snack during a quick stop? Just pull over, open the nearest side, and grab what you need. It makes loading and unloading much more flexible and less of a hassle.
Rear Hatch Access
Thule designed the Force XT with a forward position on the vehicle roof in mind. This design is specifically meant to minimize the risk of contact with your vehicle’s rear hatch when it’s opened. While vehicle designs vary, on my SUV, I can open the trunk all the way up without it hitting the back of the cargo carrier. This is a huge plus, as not being able to fully open your trunk is a common frustration with some larger roof boxes or poorly positioned setups. It means you don’t lose access to your vehicle’s interior storage just because you’ve added capacity up top.
Build Quality and Durability (with a caveat)
The Thule Force XT is made from a matte black plastic material. Upon first inspection, especially if you’re used to older, heavier-duty roof boxes, the top shell might feel surprisingly thin and flexible. This was a point of concern for me initially, echoing observations made by others. It doesn’t feel like the thick, double-walled construction you might find on some legacy models or hard coolers. However, despite this initial impression, the box has proven durable on the road. I’ve driven through heavy rain, strong winds, and at highway speeds, and the box has held up without issue, keeping everything inside dry and secure. The included tie-down straps are important for preventing items from shifting and potentially pushing up on the lid from the inside, which helps maintain the box’s structural integrity during travel. While the plastic might flex, the overall unit, when properly closed and mounted, feels solid for its intended use on the roof. The critical caveat here, and a significant downside discussed by many users, is the manufacturer’s recommendation *against* storing the box vertically on its side or end, or clamped to a wall using the internal mounts, as this can cause the plastic to deform over time, potentially impacting the lid’s fit and the locking mechanism. This limitation means you need a significant amount of floor space (75″x33″) or a dedicated ceiling hoist system for storage, which is a practical challenge for many people.
On-Road Performance (Noise and Fuel Economy)
One of the pleasant surprises with the Thule Force XT is its relatively quiet performance. Compared to experiences I’ve had or heard about with soft cargo bags that can flap annoyingly in the wind, this hard shell box is much better. While you are putting a large object on your roof, increasing wind resistance, the aerodynamic shape of the Thule Force XT keeps wind noise to a minimum under normal conditions. At speeds above 70-75 mph or in very strong crosswinds (say, over 20 mph), you will notice some wind noise, and the car might feel slightly more susceptible to being pushed around by gusts. This is inherent to any roof-mounted carrier, however, and the Force XT performs well in this regard. As for fuel economy, putting a big box on your roof absolutely impacts it. I’ve seen estimates from reviews of a 3-4 mpg decrease on highway driving, which aligns with my own observations. This is the trade-off for the extra space, and for me, the convenience of having a clutter-free and comfortable vehicle interior is well worth the slight decrease in mileage on long trips.
Security (LockKnob System)
Security is handled by Thule’s LockKnob system. This involves a central lock that engages multiple latch points (three per side on the XL) when you turn the key and the accompanying plastic knob. The integrated LockKnob is designed to make it easier to turn and also helps prevent damaging the Thule Comfort Key. A key safety feature is that the key can only be removed from the lock when the box is properly closed and all latches are engaged. This provides peace of mind knowing that if you have the key in your hand, the box is securely locked. While the system works reliably to secure the contents, I agree with other users who noted that the plastic LockKnob can feel a bit less robust, especially when trying to close a lid that might be slightly bulging from a fully packed box. You sometimes have to shift items inside or apply a bit of careful pressure to get the lid perfectly aligned before the lock will engage smoothly. The key mechanism itself can also sometimes feel a little sticky, not quite as smooth as a standard door lock. Despite these minor quibbles, the multi-point latching provides good security against theft and ensures the lid stays closed on the road.
What Others Are Saying
Looking around online, many users echo my positive experiences with the Thule Force XT, particularly the XL size. People frequently praise the sheer amount of space it adds, citing how it allows them to travel with significantly more gear, making trips with families, pets, or sports equipment much more manageable. The ease of installation thanks to the PowerClick system is another highlight, with users noting how simple and quick it is to attach securely to various crossbars, including factory racks and aftermarket systems. Many also appreciate the convenience of the dual-side opening feature. Users report that the box performs well on the road, staying securely mounted even at highway speeds and through different weather conditions, including rain.
However, the significant challenge of storing the large, flat box when not in use is a common pain point brought up in reviews, with users expressing frustration that Thule does not approve of vertical storage methods that would save precious floor space, citing potential deformation and voiding the warranty. Some also mention the top plastic feeling less substantial than expected compared to older or different models, and a few find the locking mechanism feels a bit less sturdy than they’d like, especially when trying to close a heavily packed box. Despite these criticisms, the overall sentiment is largely positive, with users generally feeling the Thule Force XT delivers on its promise of adding valuable, secure, and easy-to-access cargo space.
Final Thoughts on Gaining Extra Travel Space
Dealing with a cramped vehicle filled to the brim with luggage is a common problem for anyone who loves to travel or embark on gear-intensive adventures. This lack of space compromises comfort, limits what you can bring, and can even impact safety by obstructing visibility. A dedicated rooftop cargo box effectively solves this issue by transferring bulky items outside the cabin.
Based on my long-term use, the Thule Force XT Rooftop Cargo Box, X-Large, Matte Black is a great fit for many who need this extra capacity. It provides a generous 16 cubic feet of space, features an incredibly user-friendly and secure PowerClick mounting system, and offers the practical convenience of dual-side opening. While the storage challenge when not in use is a real consideration, its performance on the road and ease of installation make it a valuable addition for those frequent trips. If you’re tired of cramped cars and need a reliable way to bring all your gear, the Thule Force XT Rooftop Cargo Box, X-Large, Matte Black could be the solution. Click here to check it out and see if it fits your vehicle and your needs.
Last update on 2025-08-22 / Affiliate links / Images from Amazon Product Advertising API