Thule Motion 3 XL Review

The Thule Motion 3 XL is a high-end roof cargo box aimed at users who need serious storage capacity without sacrificing aerodynamics, build quality, or user-friendly features. Internally, it is 80 inches long, 29 inches wide, and 15 inches high, with a volume of 18 cubic feet. It is large enough for family gear, extended road trips, or long skis or snowboards, but carries premium pricing and size/weight trade-offs.

Ease of Use

The Thule Motion 3 XL stands out above the crowd for its ease of use. The dual-sided opening makes loading and unloading gear simple, especially when parked in a tight space or if you choose to mount the box off-center. A wire brace adds rigidity to the top lid, making it easy to open with one hand and preventing the awkward half-flop opening that is a common complaint with less refined cargo boxes.

The PowerClick mounting system makes installation quick and stress-free. Simply slot the clamps into the adjustable portals and screw the torque cogs to tighten the clamps to your crossbars. The torque makes a clicking sound when fully tightened, so you can feel confident that the box is properly fastened.

Internal tie-down straps are included for securing gear, preventing items from shifting around on bumpy roads or during sudden stops. Thule also adds a convenient reach strap attached to the inside of the lid, allowing you to pull it closed easily without the need for a stool. Our shorter testers and those with taller vehicles particularly appreciated this basic but helpful feature.

The SlideLock system is designed for simple, one-handed operation, with separate mechanisms for locking and opening. A built-in red/green indicator shows at a glance whether the box is properly closed, and the key can't be removed until it's fully locked, giving you confidence that everything is secure before you hit the road.

At 51 pounds, the Motion 3 XL is one of the heavier cargo boxes in our testing lineup. This is to be expected given its size and capacity. This does make it awkward to handle alone, so mounting or removing it is realistically a two-person job.

Security

The Thule Motion 3 XL performs well in terms of security. It uses Thule's SlideLock system, which separates the locking and opening mechanisms, giving a clear visual indication when the lid is properly closed. In addition, you can't remove the key unless the box is locked, giving you an extra level of protection against user forgetfulness.

The clamps are well-built and lock tightly around the crossbars, providing excellent protection from theft. The clamps can only be released from inside the cargo box, and because the box itself is protected by the SlideLock key system, a would-be thief cannot access or loosen the mounts without first unlocking the lid.

On the flip side, no roof box is entirely theft-proof. Although the Motion 3 XL's SlideLock and clamp system are robust, a determined thief with tools could still force entry or remove the entire box from the vehicle. For added peace of mind in remote trailheads or high-risk urban areas, many users supplement the built-in system with locking crossbars.

Quality

The build quality of the Motion 3 XL is one of its standout strengths, clearly setting it apart from cheaper cargo boxes. The shell is made from a tough ABS/polymer composite that shrugs off UV rays, snow, rain, and freezing temperatures with very little warping or flex over time. This makes it a true four-season hauler you can rely on for years of use.

The glossy finish does show scratches more readily than matte designs, but these are cosmetic and don't compromise the structure. Every component—from the reinforced lid and smooth hinges to the sturdy latches and mounting hardware—feels precise and confidence-inspiring. The rigid lid opens cleanly without wobble, and the slide lock mechanism clicks with authority.

We have heard users complain that the slide lock system can be hard to open if the box has been out in particularly damp freezing conditions, but this was not a problem we encountered during testing.

Appearance

The Motion 3 XL is visually appealing, sporting a sleek, aerodynamic silhouette. Clean lines and glossy finishes (Titan Glossy, Black Glossy) add to its premium look. The shape is modern and minimizes bulk while still providing volume; the design manages to look “integrated” rather than just bolted on.

It's not perfect: the gloss finishes may show scratches or scuffs more conspicuously than matte or textured finishes. Also, because of its size, it dominates the roof visually (especially on smaller vehicles), possibly altering vehicle aesthetics depending on one's taste.

Should You Buy the Thule Motion 3 XL?

This cargo box is ideal for families, skiers, and long-haul adventurers seeking a secure, aerodynamic hauler that can accommodate everything from duffels to 200 cm skis, while still opening smoothly from either side and locking with confidence. If you only intend to store skis or other non-bulky items, Thule offers a low-profile version of the Motion 3 XL is lighter and allows for better clearance. This version we tested is best for those who want maximum capacity, premium features, strong security, and a polished look, and are willing to pay for—and live with—the added weight, bulk, and cost

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