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Trunx Rooftop Cargo Box - 18 cu ft - Black

Trunx Rooftop Cargo Box - 18 cu ft - Black

Item # TRX34FR
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Our Price: $322.90
Roof Box
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Shipping Weight: 37 lbs
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56-1/2 x 38-3/4 x 19. Roof box mounts to your crossbars with U-bolts and hand knobs. Locking lid opens from the rear. Carries camping gear, sports equipment, and other cargo on larger CUVs and full-size SUVs. Durable, HDPE thermoplastic construction. Lowest Prices for the best roof box from Trunx. Trunx Rooftop Cargo Box - 18 cu ft - Black part number TRX34FR can be ordered online at or call 1-800-940-8924 for expert service.
  • All Info
  • Reviews (7)
  • Q & A (0)
  • Photos
  • Why etrailer?

Trunx Roof Box - TRX34FR

  • Aero Bars
  • Elliptical Bars
  • Factory Bars
  • Round Bars
  • Square Bars
  • Large Capacity
  • Trunx
  • Short Length
  • Black
  • Passenger Side Access
  • High Profile

56-1/2 x 38-3/4 x 19. Roof box mounts to your crossbars with U-bolts and hand knobs. Locking lid opens from the rear. Carries camping gear, sports equipment, and other cargo on larger CUVs and full-size SUVs. Durable, HDPE thermoplastic construction.


  • Cargo box mounts on your vehicle's roof rack to provide enclosed storage for your gear
    • Perfect for carrying sports equipment, camping gear, or luggage for up to 4 people
    • Great for most full-size SUVs and larger CUVs
  • Rear-opening lid lets you load and unload gear from the passenger's side of your vehicle
    • 2 Metal struts hold the lid open
  • Built-in lock secures gear in box and secures box to crossbars
  • Latches on front, rear, and driver's side of box ensure lid is completely closed
    • Can be locked with padlocks (not included) for added security
  • Tool-free installation with included U-bolts, hand knobs, and plates
  • Aerodynamic shape helps minimize wind noise and drag
  • Compact storage - removable lid nests in base when not in use
  • Durable, HDPE thermoplastic construction
  • Matte black finish
  • Made in the USA


  • Application: most round, square, aero, elliptical, and factory crossbars
    • Maximum crossbar dimensions: 3-3/4" wide x 1-3/16" tall
  • Crossbar spread: 22"
    • Can be expanded to a maximum of 31" (requires drilling)
  • Carrying capacity: 18 cu ft
  • Weight capacity: 100 lbs
  • External dimensions: 56-1/2" long x 38-3/4" wide x 19" tall
  • Internal dimensions: 56-1/3" long x 38-1/3" wide x 18-1/3" tall
  • Box weight: 29 lbs
  • Limited lifetime warranty

Car Top Cargo logos

Mounting Diagram

TRX-18L Trunx Roof Cargo Carrier - Large - 18 cu ft - Black

Replaces Car Top Cargo CTC-18S

Customer Reviews

Trunx Rooftop Cargo Box - 18 cu ft - Black - TRX34FR

Average Customer Rating:  3.0 out of 5 stars   (7 Customer Reviews)

56-1/2 x 38-3/4 x 19. Roof box mounts to your crossbars with U-bolts and hand knobs. Locking lid opens from the rear. Carries camping gear, sports equipment, and other cargo on larger CUVs and full-size SUVs. Durable, HDPE thermoplastic construction.


Save your money and do not buy this product, it's poorly manufactured to say the least. 1), the plastic gauge is way to thin making the final product to flimsy. 2) while the order information asked me for make, model and year of vehicle it did not match factory rail specifications. The factory roof rack system for Honda CRV is not adjustable and the 22 inch spread identified for product does not work for Honda installed roof rack systems. 3) lastly, the hinge design on this unit is poorly designed and will not align without modifications to bend the tabs so that they properly align with the slots.

Once again, do not waste your money on this product.

This rooftop cargo box can accomodate up to a 30 inch spread on some crossbars, but it would involve drilling to the custom measurements of your CR-V crossbar spread.
-- Etrailer Expert Rachael H - 09/17/2019


Put it together in just a few minutes. Very easy. Haven't actually mounted it to the car yet. In my case, I think side opening would be preferred as the Traverse is very tall and will require a small step ladder to reach the lock.


I am not completely satisfied with this product, although it holds things ok. Made of plastic that is very flimsy/flexible. Would be better if it was rigid plastic. Also find the support holders are a bit difficult to put onto the little pegs (can't really see them do to being inside). Purchased for our make and model and still had some difficulty installing. Was not pleasant and I usually enjoy doing projects.


I have a 1 star because I am very disappointed in the quality . The plastic
Cover is badly warped out of the box making it very difficult to close. For the price of this product I am dissatisfied with the quality.


The roof top box is definitely big enough for my all my family's gear, planning a road trip out West that includes some camping along the way.

The plastic was a bit flimsier than I had expected and I was NOT impressed with the PLASTIC clamps around the side. I'm not too worried of the lid flying off if a clamp or two breaks - the front of the box locks and there is a pin in the rear hinge - however, I'm packing extra rope just in case. It also appears that the rivets holding the rails and lock to the container are also made of plastic.

I do a lot of camping, I'll likely update my review after putting it through a few runs.


by: 07/15/2021


Ask the Experts about this Trunx Roof Box

  • Trunx Rooftop Cargo Box that Can Fit Cargo that Measures 39x12x11.5
    Due to the taper on the sides of the front of the Trunx Rooftop Cargo Carrier # TRX44FR it would not fit your cargo, so you'd need to go with the larger size part # TRX34FR.
    view full answer...
  • Will the Trunx Rooftop Cargo Box Fit for a 2017 Audi Q5 with 28 Inch Crossbar Spread
    The Trunx Rooftop Cargo Box - 18 cu ft - Black # TRX34FR comes setup for a 22" crossbar spread but can be expanded out to 31", so it will work for your 28" spread. You will need to drill new holes and the method that you've mentioned will work well to fit this to the crossbars on your 2017 Audi Q5.
    view full answer...
  • Will Trunx Cargo Box Fit a 2017 Toyota Highlander with 23 Inch Bar Spread?
    As long as your crossbars are less than 3-3/4" wide x 1-3/16" tall you would still be able to use Trunx # TRX34FR on your 2017 Toyota Highlander. However, this does require drilling new U-bolt holes in order to accommodate your 23 inches of bar spread.
    view full answer...
  • What Roof Cargo Box that Can Fit Crossbar Spread of 30-1/4 Inches
    Since there isn't a safe way to modify or adapt the Sportrack roof box you have to fit the wider crossbar spread you have the best solution we have would be a new cargo box that is compatible with that spread. The most similar solution we have would be the Trunx Rooftop Cargo Box - 18 cu ft - Black # TRX34FR which can have it's mounting holes redrilled to fit your crossbar spread of 30-1/4 inches. This box also has the same cubic footage as the SportRack # SR7095.
    view full answer...
  • Will SportRack SkyLine XL Cargo Box Fit 2018 Chrysler Pacifica With Factory Crossbars
    We do have a cargo box that will work for your 2018 Chrysler Pacifica with the factory roof rack, but according to my research, the SportRack SkyLine XL Cargo Box # SR7095 will not fit. A cargo box at a similar price point which I can confirm will fit is the Trunx Rooftop Cargo Box # TRX34FR which will fit crossbar spreads from 22" to 31" but will require drilling new holes in the bottom of the box to get the U-bolts to mount to your Pacifia's crossbar spread. Like the SkyLine, the Trunx...
    view full answer...
  • What is the Largest Cargo Box that Will Fit a 2020 2020 Toyota 4Runner TRD Pro?
    The largest roof cargo carrier we have that will fit the 46 inches from the front crossbar to the line where the roof and the hatch meet (in order to open the rear hatch) is the Trunx Rooftop Cargo Box - 18 cu ft - Black # TRX34FR with interior dimensions of 56-1/3 inches long x 38-1/3 inches wide x 18-1/3 inches tall. The Trunx Rooftop Cargo Box will fit on your factory crossbars with a maximum width of 3-3/4 inches and a maximum height of 1-3/16 inches. The Trunx Rooftop Cargo Box is...
    view full answer...
  • Will The Thule Vector M Roof Cargo Box Fit My 2021 Mazda CX5 With Factory Roof Rack?
    The Thule Vector M Rooftop Cargo Box - 13 Cubic Ft - Titan Matte Gray # TH613200 will fit your crossbars just fine on your 2021 Mazda CX-5. Keep in mind, in order to allow your rear hatch to open properly there must be at least 47-1/2" from the center of the front crossbar to the line where the roof meets the hatch. It looks like your vehicle should have 48" from the from crossbar to the hatch so it should work find but it will be close; I recommend measuring to verify. In regard to the...
    view full answer...
  • Will the SportRack SkyLine Cargo Box Fit on Factory Crossbars of a 2018 Kia Sorento
    Yes. The Trunx Rooftop Cargo Box - 18 cu ft - Black # TRX34FR is designed to fit on most aftermarket and factory roof rack crossbars, so as long as your 2018 Kia Sorento's factory bars aren't wider than 3-3/4" this box will fit without any issues. Most crossbars aren't that wide and I have yet to encounter a factory crossbar that this box hasn't fit on, so the Trunx cargo box will do a great job.
    view full answer...
  • Roof Cargo Box that Can Fit 2021 Toyota Sienna with OEM Crossbars
    The Trunx roof top cargo box part # TRX34FR can fit the crossbars of your 2021 Toyota Sienna but you would need to drill new holes in the box unless your crossbars can be placed right at 22 inches. Basically any roof cargo box will fit your vehicle but if you wanted something a little nicer yet in same price range the Malone Profile18s part # MPG910 would be a really great option. It has a sleaker design, opens from the side, and has easier to use mounting hardware as well.
    view full answer...
  • Will the Yakima SkyBox 21 Fit My HD Bars on Our Trailer?
    I have a great cargo box solution for you. Without knowing the exact model or dimensions of your HD bars on your trailer, the Yakima SkyBox 21 # Y07337 will fit if the crossbars do not exceed 3-1/2 inches wide x 1-11/16 inches tall. In order to confirm if they fit or not, I recommend measuring your crossbars. If you discover that the SkyBox 21 will not fit your bars, there is unfortunately no HD adapter that will allow you to fit the clamps around the crossbars. The only other rooftop...
    view full answer...
  • Is There A Rooftop Cargo Box That Is Big Enough For My Pit Barrel Jr. Smoker
    The Malone Cargo12 Rooftop Cargo Box - 12 cu ft - High Gloss Gray, part # MPG901, does narrow from back to front. I do not think the Pit Barrel Jr Cooker will fit inside this Malone Cargo 12. The interior dimensions of the Malone Cargo 12 are L - 52.1" X W - 28.5" X H -16.3". My recommendation is the Trunx Rooftop Cargo Box - 18 cu ft - Black, part # TRX34FR. The 18' Trunx rooftop cargo box is not a traditional aerodynamically shaped rooftop cargo box. It is more blocky in shape. You will...
    view full answer...
  • Can I Drill Holes in the Trunx # TRX34FR to Accomodate a 38.5 Inch Bar Spread?
    I have cargo solution for you. While it may technically work to drill holes for the mounting hardware of the Trunx Cargo Carrier # TRX34FR, the manufacturer does not recommend drilling holes to accommodate a crossbar spread over 31 inches. Since we do not know the exact Yakima crossbars you have on your roof rack, the Trunx carrier will clamp around the bars as long as they do not exceed 3-3/4" wide x 1-3/16" tall. I recommend measuring the height and width of your crossbars to make sure...
    view full answer...
  • Can I Drill Holes into the Trunx # TRX34FR with a Crossbar Spread Longer than 31 Inches?
    I have a great rooftop box option for you, but we do not recommend drilling into the Trunx Cargo Box - 18 Cu Ft. # TRX34FR with a 32-1/2 bar spread. This is because the maximum allowed crossbar spread for the # TRX34FR with drilling is 31 inches apart. It is always strongly recommended not to exceed any limits put in place by the manufacturer because doing so can not only cause damage and void warrantees; it can also be dangerous. On top of that, we have not installed the # TRX34FR with...
    view full answer...
  • Are There Tie-Down Ratchet Straps I Can Use On My Trunx Rooftop Cargo Box For Extra Security?
    We do have tie-down straps for added security when mounting your Trunx Rooftop Cargo Carrier - 9 cu ft - Black # TRX44FR or Trunx Rooftop Cargo Box - 18 cu ft - Black # TRX34FR to the roof of your 2021 Jeep Grand Cherokee. I recommend getting Erickson Sliding Ratchet Tie-Down Straps w/ Safety Hooks - 1" x 14' - 400 lbs - Qty 2 # EM97JR which will suite your needs well. I have attached demonstration videos for you to check out.
    view full answer...
  • Will the Inno Wedge 660 Fit on my Platform Roof Rack on My 2021 Toyota 4Runner?
    I have a great cargo box solution for you. Unfortunately, we do not have the exact measurement of the vertical underbelly of the front and rear of the Inno Wedge 660 - 11 cu ft. # INBRM660BK. However, for a solution that has absolutely no extra height added underneath that interferes with your roof on your 2021 Toyota 4Runner, I recommend the Trunx Rooftop Cargo Box - 18 cu ft - Black # TRX34FR. With the Trunx, you will not have to worry about vertical clearance on your roof and the Trunx...
    view full answer...
  • Durability Of SofTop Roof Top Cargo Carrier
    The Advantage SportsRack SofTop Rooftop Cargo Bag # HE3021 bag can be mounted and secured to the top of your horse trailer. That being said the bag is not waterproof per 0:40 of the video and water can get through the zipper potentially so these factors could cause the bag to not be ideal for all the time, permanent use. The bag may be more ideally used and then stowed away when not in use as it could wear down in the elements. An upgraded bag like the Rhino-Rack Rooftop Cargo Bag #...
    view full answer...
  • Crossbar Spread Required for Trunx Rooftop Cargo Box
    I'm certainly sorry to hear about the cargo bag issue you had going through a snow storm. Cargo bags are really handy and easy to manage but weather can be an issue so you are smart to go with a cargo box. The Trunx Rooftop Cargo Box # TRX34FR you referenced uses U-bolts that will work on crossbar spreads from 22 inches to 31 inches and the spread of the SportRack Roof Rack # SR1010 on your Ford Fusion is going to be in that range so it is definitely going to work. The cargo box will...
    view full answer...
  • Replacement Mounting Hardware for Sears Sport SP-20SV Rooftop Cargo Box
    We have replacement mounting hardware for a Sears Sport SP-20SV cargo box, but the Replacement Mounting Hardware for Car Top Cargo Roof Cargo Box # CTC-18PARTS is only a fit for the Trunx Rooftop Cargo Box # TRX34FR. The correct mounting hardware for the SP-20SV is the Replacement Hardware Kit for Searsbox Cargo Box # TH05603. We don't carry that cargo box, and we would be unable to confirm any specific fits, but I believe it is a universal fit so there's no reason to think it won't fit...
    view full answer...
  • What Roof Rack System and Rooftop Cargo Box Will Work on Factory Flush Rails on a 2016 Lexus GX 460?
    I have a solution for you. Yes, the parts that you listed are correct for a complete roof rack system on your 2016 Lexus GX 460. However, the crossbar dimensions of the Inno Aero Crossbars # INXB123-130 are not compatible with the Malone Profile18S Rooftop Cargo Box - 18 Cubic ft - Gray # MPG910. Since the Profile18S requires a crossbar width between 1-3 inches, it is not compatible with the 3-1/8 inch wide Inno Aero Crossbars. With that being said, I recommend the Trunx Rooftop Cargo...
    view full answer...
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  • Compatibility of CAM-Locks and Thule Boxes
    The CAM-Lock cores like part # CTC-CAMLOCK-18M-2874 are designed for the Trunx Rooftop Cargo Box, part # TRX34FR. As such, I cannot say if they will work with your Thule box or not. Thule has their own line of lock cores for their products. If you let me know which Thule core you have or which cargo box you have, I can help you find the correct replacement core and key.
    view full answer...
  • Low Cost Rooftop Cargo Box Alternative to Replace Thule Force
    Although we do offer a lot of replacement parts for rooftop cargo boxes such as the Thule Force XT # TH6356B they do not offer only the top/lid portion of any of their cargo boxes as a stand-alone replacement part. We do have the Force if you want to order the same unit but if you would prefer a lower-cost cargo box to replace the Force XL we can help you with that too. For example, Trunx offers their 18-cubic-foot box # TRX34FR. This offer slightly more volume capacity than the Force...
    view full answer...
  • Recommended Cargo Box for 2019 Toyota RAV4 That Doesnt Obstruct Roof Antenna
    In order to use the Thule Motion XT # TH629706 on your 2019 Toyota RAV4 you're going to need 47-1/2" from the center of your front crossbar to the crease where the roof and the hatch meet. However, it's going to be substantially less than that when it comes to the antenna, so using a long box like this likely isn't going to be the best solution because you're likely going to see some reception issues if it's covered. I recommend considering the Trunx Rooftop Cargo Box # TRX34FR, since...
    view full answer...
    Image 1 for
  • Recommended Roof Rack For Carrying A Cargo Box On A 2022 Kia Telluride With Flush Rails
    To get the Trunx Rooftop Cargo Box # TRX34FR mounted on the top of your 2022 Kia Telluride, I recommend going with the Rhino Rack Vortex Aero Crossbars # RRVA137B-2 and SX Series Legs # RR94DY. This will attach directly to the flush rails on your roof and give you 54" of space and 165 pounds of capacity. The Trunx cargo box will have absolutely no issue connecting to these bars and said bars are easily removed when not in use, so it is highly recommended.
    view full answer...
  • What Options Do I Have for a Mounting a Cargo Box and a Basket at the Same Time on My 2020 4Runner?
    I have a solution for you. Unfortunately, we do not currently carry crossbars that are long enough that are recommended for your 2020 Toyota 4Runner that will let you attach the Trunx Rooftop Cargo Box - 18 cu ft - Black # TRX34FR along with your 33-1/2 inch long x 49 inch wide cargo basket. Also, we currently do not carry any hard cargo boxes that will allow you to safely attach it to your basket. With that being said, if you remove your cargo basket, the Trunx cargo box will fit your...
    view full answer...

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Info for this part was:

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