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Thule Force XT XL Rooftop Cargo Box - 18 cu ft - Black AeroSkin

Thule Force XT XL Rooftop Cargo Box - 18 cu ft - Black AeroSkin

Our Price: $801.05
Roof Box
Shipping Weight: 50 lbs
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82-3/4 x 33-3/4 x 17-1/4. This aerodynamic, low-profile cargo box holds outdoor equipment and large luggage for up to 5 people. Quick-Grip clamps let you quickly mount the box to your roof rack, and the locking lid opens from both sides. Great Prices for the best roof box from Thule. Thule Force XT XL Rooftop Cargo Box - 18 cu ft - Black AeroSkin part number TH6358B can be ordered online at or call 1-800-940-8924 for expert service.
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  • Reviews (303)
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  • Used (1)

Thule Roof Box

  • Aero Bars
  • Elliptical Bars
  • Factory Bars
  • Square Bars
  • Round Bars
  • Large Capacity
  • Thule
  • Long Length
  • Black
  • Dual Side Access
  • High Profile

82-3/4 x 33-3/4 x 17-1/4. This aerodynamic, low-profile cargo box holds outdoor equipment and large luggage for up to 5 people. Quick-Grip clamps let you quickly mount the box to your roof rack, and the locking lid opens from both sides.


  • Low-profile, roof-mounted cargo box provides enclosed storage for your gear
    • Perfect for outdoor equipment, large luggage and baby gear for up to 5 people
    • Great for mid-size wagons and crossovers
  • Pre-installed Quick-Grip mounting clamps provide 5-minute installation on your crossbars
    • Simply turn dials to secure mounting clamps to roof rack
    • Integrated PowerClick torque indicator clicks when clamps are properly tightened
  • Aerodynamic shape helps to reduce drag and wind noise
  • Dual-side-opening lid lets you load and unload gear from either side of your vehicle
    • Hand knob on lock makes lid easy to lift and close
  • Oversize SecureLocks ensure that lid is closed and locked
    • Key can only be removed when box is properly closed and locked
    • 2 Thule One-Key System locks included
  • 2 Load straps connect to built-in anchor points on Quick-Grip hardware to secure your gear
  • Rugged ABS plastic construction resists impacts, weather and harsh UV rays
  • Black AeroSkin diamond-texture lid and base looks stylish on your roof
  • Made in the USA


  • Application: round, square, aero, elliptical, and most factory crossbars
  • Maximum crossbar dimensions: 3-1/2" wide x 1-11/16" tall
  • Crossbar spread: 23-5/8" - 35-7/8"
  • Carrying capacity: 18 cu ft
  • Weight capacity: 165 lbs
  • Hatch clearance: 51-1/8"
  • Ski/snowboard capacity: 5 - 7 pairs of skis or 3 - 5 snowboards
  • Maximum ski/snowboard length: 194 cm
  • Dimensions:
    • External: 82-3/4" long x 33-3/4" wide x 17-1/4" tall
    • Internal: 77-1/2" long x 29-1/2" wide x 15-1/4" tall
  • Box weight: 47 lbs
  • Limited lifetime warranty

Cargo Box Clearance Dimensions

635801 Thule Force XT Extra-large Roof Mounted Cargo Carrier - 18 cu ft - Black AeroSkin

Replaces Thule TH625 and TH6358B

Item # TH6358B

Installation Details TH6358B Installation instructions

Customer Satisfaction Score:

Customer Reviews

Thule Force XT XL Rooftop Cargo Box - 18 cu ft - Black AeroSkin - TH6358B

Average Customer Rating:  4.8 out of 5 stars   (303 Customer Reviews)

82-3/4 x 33-3/4 x 17-1/4. This aerodynamic, low-profile cargo box holds outdoor equipment and large luggage for up to 5 people. Quick-Grip clamps let you quickly mount the box to your roof rack, and the locking lid opens from both sides.


I’ve been owning this cargo box for over a year now , I love it and never had problems at all or any issues . Handles in weathers, power washing and high speed winds . Very sturdy and good looking cargo box


This cargo box fits well on our Toyota Sienna. It is lightweight but awkward for one-person handling. I would say that the hinge mechanism is novel and well designed. Due to the length and flexibility of the box itself, opening and closing can feel floppy before the box is secured to the roof.
We have only used this twice in the past year, on two 1,000 mile trips. One included a sustained, driving rainstorm. All of our luggage stayed dry. There is minimal wind noise. Due to much higher weight (passengers, luggage) and greater tire inflation, I can't quantify the fuel economy impact. Our Sienna averaged 25 mpg while driving 75 mph on the interstate.


It was exactly as I had envisioned. I can’t wait to take it out on a trip to see if it performs as expected.



I have had the roof box for a year, It has worked as hoped, easy to install, holds a lot more gear and is efficient with opening to both sides. I am very pleased with it.


We've only used our Thule a handful of times since purchasing it a year ago. But as a family of 4 we can place all 4 of our carryon luggage's in the the Thule and still have plenty of room to stow extra shoes and drinks, leaving the interior of the car clutter free and room for the kids to stretch out. Mounted on a 2020 Toyota Highlander


Love how rugged this thing is. Been in a couple storms and everything stays safe, secure, and dry.

I still give this a 5 star but if you are looking for a con. The only thing that needs improvement is the locking system. It works and secures everything as it should, but when the carrier is full of stuff its difficult to get the latches to grab correctly. After doing this a bunch ive gotten the hang of it but if you ever need to push down on the top a bit to latch it you will know what im talking about. Just make sure hte locking pins are totally clear inside.

Would buy this again 5/5


We just came back from a 2000+ mile trip from Maryland to the Gulf Shores. This cargo box worked flawlessly. The extra 18 cu ft of storage contained 3 carryon bags, 1 large suitcase, fishing gear, a small tent and an acoustic guitar. Had initially ordered the Yakima Grand Tour but it was backordered till next year. etrailer was able to provide other options and after comparing 6 boxes, this box was selected for its larger capacity, dimensions, price and aesthetics (it looks like an escape pod for some spacecraft). The length is longer than the Yakima but the frontal area (which is more important for range) is slightly lower and narrower. Mounting it on the factory crossbars was very easy. It takes only minutes to install or remove. The initial installation took the longest as I wanted to make sure it was centered before I marked the crossbars to make the next install easier. The box does flex a little on bumpy roads as we can see the front from our windshield but there were no issues driving in the low 80 mph range.


Where do I even begin to extol the virtues of the Thule Force XT XL Rooftop Cargo Box? This powerhouse of a cargo box is an absolute game-changer for the road-tripping, adventure-loving enthusiasts.

To start with, the design is sheer brilliance. The Thule Force XT XL is not just another cumbersome rooftop cargo box; it is a sleek, aerodynamic wonder that looks as good as it performs. It is an ideal fusion of aesthetics and functionality, with its diamond-textured AeroSkin lid that helps reduce drag and wind noise. You'll hardly know it's there!

The Thule Force XT XL Rooftop Cargo Box offers an impressive cargo capacity of 18 cubic feet. Despite its generous size, it never feels bulky or unwieldy. Whether you're packing up for a cross-country road trip or a weekend getaway to the mountains, this cargo box will swallow up everything you throw at it – luggage, camping gear, skis, snowboards, and more.

What really sets the Thule Force XT XL apart is the intuitive, user-friendly design. The dual-side opening is a revelation - no more struggling to reach your items from one side. And talk about ease of installation! The FastGrip quick-mount system is so simple and secure; you'll have it on your roof and loaded up in no time.

The locking system is foolproof, providing a level of security that is comforting when you're on the road. Each box comes with the Thule One-Key system, which ensures your belongings are protected and secured. Say goodbye to those sleepless nights worrying about the safety of your gear.

The durability of the Thule Force XT XL is phenomenal. It has stood up against all weather conditions during our travels - blazing sun, heavy rain, and even a hailstorm. The box remained dry and the contents untouched, a testament to its high-quality construction.

As for the customer service experience with Thule, it's nothing short of top-notch. Their support team was responsive, knowledgeable, and always ready to assist. This company stands by their products and it shows.

Finally, for the environmentalists out there, you'll be pleased to know that the Thule Force XT XL is made from ABS plastic, which is recyclable. It's nice to know that Thule is not only thinking about our immediate needs but also the impact on our planet.

In conclusion, the Thule Force XT XL Rooftop Cargo Box is, in my opinion, an extraordinary investment. Its premium quality, design ingenuity, and generous capacity make it an essential companion for any road trip. We couldn't be happier with our purchase and I have no doubt that you will feel the same. It's safe to say that this is one product that definitely lives up to the hype.


The Rooftop Carrier has been everything we expected.

David M.


The product works like it did when new. I use it 4-6 times during yr. Easy on and off. Must have key to open the unit in order to install or remove. No special tools required.


Open / close mechanism works well. Nice to be able to open the box from either side. We have a Hyundai Sonata and this size is ideal.


The locking mechanism is VERY difficult to use, not sure if it is a defect with my box or a common problem. Also, you have to make sure it is aligned perfectly at three different points when closing, or the lock won't even engage. I have had to ask several strangers to assist me in locking/unlocking and loading up after a long ski day. Not user-friendly for one person.

Etrailer Expert

Jenny N.


I reached out to the manufacturer who will be in contact with you.


A little more flimsy than I had hoped. I know, Thule is trying to save weight, okay. The clasp devices that holds the cargo box in place is worth the price. They are so easy to adjust and are very secure. Also, the ability to open the box from either side of the SUV is also worth the purchase price. Everything inside stayed dry in heavy rain. I really like the finish on the box. Good Product!

Roger S.


After a year, Im more convinced I made the right choice. Engineered to last.


Another "made in the USA" quality packing failure. $[XX] flat pack furniture has better packaging protection than this $[XX] cargo box. The cargo box arrived in a loose-fitting thin cardboard box lick taped with one small piece of tape holding it closed (I think the shipper put it on to keep it closed). Several impact dents on the cargo box and a bent frame. The frame was not noticeable until after unlocking the cargo box. At least the cargo box was in a clear bag to keep it dust free. A little extra cardboard packing with foam would go a long way in protecting this item. I bought it new so would like it in new condition. Thule’s or etrailer’s packing department should expect rough handling while in shipment. All damage would have been preventable with the extra protection.

Brooke M.


I have sent your information to our customer service team. I am so sorry this happened and I am confident our customer service team will be able to work with you. Thank you for letting us know.


Super easy to install. etrailer delivered on time. Easy to work with. We were able to put 3 pairs of AT skis, 2 pairs of downhill, 3 pairs of backcountry skis and 3 pairs of snowshoes plus poles in at once. It all fit. A little tricky and would not recommend unless it was an absolute requirement. Everything was well secured and weight was below the limit.


Finally was able to use the box for Christmas. It worked very well and we took it off and put it back on during the vacation.
this is made much easier by being able to open the box on either side.


Do not buy this unless you want to spend 5mins+ every time you shut the lid. The locking mechanism is frustratingly horrible! On a positive note the available cargo space is amazing, it sits solid on the roof of my 4runner and it is impressively quiet on the highway. Unfortunately the difficulty in getting it to latch shut negates all of the positives.


Definitely very useful on a minivan loaded with people and gear. The hinging system is "ok". It likes to come apart when opening if the lid is not lifted exactly even. Its a small issue, more of an annoyance. Over all well worth the investment for traveling


Installs easy. Quiet on the road. Very sturdy. Used several times in rain, snow and very hot weather. No issues. Also made in USA!


Remarkably easy to install - in less than five minutes. My wife and I easily lifted it in place, applied the attachments and were ready to go. Conveniently opens from either side. Able to adjust front to back and side to side to get to the optimal position on the roof rack. Even positioned as far to the rear as possible, the back gate of our Honda Odyssey opens with about two inches of clearance. Looking forward to our first loaded road test.



One year in and still loving it. Extra storage for a cross-country move, tents and sleeping bags, ski equipment, you name it-it fits. Easily handled skis, poles, boots and helmets for a family of six. No visible wear and tear and works as well as the first time. Definitely a good investment.


This is a larger roof box, but it fit just fine on our Subaru Forester. Holds a lot of gear for camping, and it's long enough to carry cross country skis too.


Outstanding service and overall great experience! Had to cancel one due to back order, switched it to the Force XT with no problems. Great experience!


With every single penny of it. The best. Very satisfied after owning it for a year.


I like the unit however the keyed lock is substandard. It hangs up in the unlocked position and do I have to jiggle it a lot to get it to lock back up.


This Thule box has been great. It may not be the cheapest one out there but it's easy to install and all the mechanical functions are high quality. We have used this a number of times over the past year and I can store enough luggage in here for 5 people over the course of at least a week. Great for skis too.


Made many road trips with this guy and it’s never leaked and never had any problems. Occasionally it’s hard to shut but that is more my fault for overloading it a bit.


Quick delivery for a large package

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Used Picture for Thule Force XT XL Rooftop Cargo Box - 18 cu ft - Black AeroSkin

Condition: Surface Scratches

Notes: Item has a minor scuff/scratch on the top. Otherwise new adn unused.

Our Price: $739.60
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