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Replacement Mounting Hardware for Trunx Roof Cargo Box

Replacement Mounting Hardware for Trunx Roof Cargo Box

Item # CTC-18PARTS
Our Price: $27.08
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Shipping Weight: 1.08 lbs
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This kit replaces the mounting hardware for your Trunx roof cargo box. Includes 4 U-bolts, 4 spacers, and 8 knobs. 1-800-940-8924 to order Trunx accessories and parts part number CTC-18PARTS or order online at Free expert support on all Trunx products. Great prices and Fastest Shipping for Replacement Mounting Hardware for Trunx Roof Cargo Box. Accessories and Parts reviews from real customers.
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  • Reviews (118)
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Trunx Accessories and Parts - CTC-18PARTS

  • Roof Box
  • Mounting Hardware
  • Trunx

This kit replaces the mounting hardware for your Trunx roof cargo box. Includes 4 U-bolts, 4 spacers, and 8 knobs.


  • Replaces the mounting hardware for Trunx roof cargo boxes
    • Fits model CTC-18S
  • Includes 4 U-bolts, 4 plates, and 8 hand knobs

CTC-18PARTS Replacement Mounting Hardware for Trunx Roof Cargo Box

Video of Replacement Mounting Hardware for Trunx Roof Cargo Box

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Review of Car Top Cargo Roof Box Parts - Mounting Hardware - CTC-18PARTS

Ellen: Hey everyone. I'm Ellen here at Today, we're taking a look at the replacement mounting hardware for Car Top Cargo Roof Cargo Box.This is going to be that attachment hardware to get your roof cargo box secured to your roof rack on your vehicle. This can also work with several different older style roof cargo boxes out there, so I'm going to go over the measurements here to make sure that this is going to be a fit for your application.Basically, what comes in our kit, we'll get our four straps, or our four just flat brackets and then four of these . almost like a parentheses brackets shaped bracket. It's got that little notch there.

It'll work with several different bar styles, if it's round, square, elliptical, or anything else. And then we'll get our eight wing knobs or wing nuts to tighten those down. There are also four clips that come with it, just little spring safety clips.As far as the measurements go for our plates, the overall length for each of these is 5", going from that rounded end to rounded end. The distance between the mounting holes center to center is 4". The width is right at 1" and the thickness is about 1/8".

The diameter of those holes for each of our brackets is about 5/8", or excuse me, 5/16", maybe just under, or just about 1/4", which matches up, of course, with our U-bolts. The outside distance for each of these is going to be 4-1/4", so from outside edge to outside edge. The distance between these center to center, though, is going to be 4", which again matches up with our plate there. The diameter of those U-bolts is about 1/4". The length here on the side is about 1-3/4".

The overall height or depth, however you want to look at it, is about 2-1/2", going from the end of that little notch to the end of the threads. And then our wing knobs are about 1" tall and about 1-1/4" or 1-1/2" at the longest point.Now, this fits the Car Top model CTC-18S, but again, it does fit several other cargo boxes out there so it can be used for other applications. You just want to be sure that whenever you're tightening these, this hardware down on your roof, that you kind of go back and forth to make sure that everything's pulled down appropriately. You want to make sure that you kind of alternate each, from one to either side, so that you're not tightening one side more than the other.But that's basically going to do it for our look at the replacement mounting hardware for Car Top Cargo Roof Cargo Box.

Customer Satisfaction Score:

Customer Reviews

Replacement Mounting Hardware for Trunx Roof Cargo Box - CTC-18PARTS

Average Customer Rating:  4.8 out of 5 stars   (118 Customer Reviews)

This kit replaces the mounting hardware for your Trunx roof cargo box. Includes 4 U-bolts, 4 spacers, and 8 knobs.


Worked PERFECTLY for older off brand roof carrier. I bought a Reese Carry Power (still sold on Amazon and at Walmart) carrier at a second hand store for pennies. It came with no hardware. etrailer had a video that provided the specs and measurements for their hardware and it was close enough. Installed in less than 10 minutes and it is rock solid. Drove it around town for a couple of days in preparation for eight hour vacation drive and am 100% confident. Order was filled and shipped the next day and arrived in two days. Received email notices when order placed, filled and shipped. Highest satisfaction and rating available. Quality company and quality product.

One year later, two trips to the beach and one to the mountains, and still rock solid! Easy to use hardware that works perfectly.
Michael - 07/20/2021


The replacement hardware for my Sport15-CAV luggage carrier was very secure on my roof bars (Rola Sport Series Roof Rack with GTX Mounting System for Naked Roofs, purchased from etrailer for a great price). I did move the rear bar back slightly to fit where the holes needed to be to fit the luggage carrier. To install the hardware, I used a 1/4" drill to make the holes. The V wrapped under the roof rack bars with the screws pointing upward through the roof carrier. The metal bars were inside of the carrier. I also want to mention that I was able to obtain a replacement key for my luggage carrier from eTrailer. It is wonderful to be able to use the luggage carrier again!

Still working great!
Betty B - 12/19/2021


Drilled a few holes in this older x-cargo because I was sick of the straps. Works perfectly.


Very solid. I'm actually using it to mount my Thule ski set up to my Toyota factory aerobars.


I bought the hardware to mount a Yakima Space Booster. The hardware fit perfectly without the need to drill additional holes. Brackets are made with nicely weighted steel. The twist nuts are okay. I just wish that they were larger in diameter for my hands. The reinforcement plates are coated with zinc to mitigate rust whichbis a nice touch. Looking forward to seeing how well it "holds" up on our trips. Luckily the factory rails on our RX 350 were able to be adjusted forward by removing the bumper stops to accommodate the long Yakima. The liftgate still touches the Space Booster but that's something that I can tolerate for now.


Works exactly as advertised. Great communication w/ eTrailer.


I was able to drill two small holes in my old cargo carrier for each bracket. It works perfectly!


Everything was great. I ordered a new key for my cargo box. I got it at a thrift store. I was worried about it not working. As soon as I got the order I tried it and it worked I was very happy!


We had assistance in ordering the correct parts, the cost was in line and shipping was promised with product delivered timely.coukdbt be more pleased!!! We repaired our cargo carrier to like new and saved a bundle


Worked perfectly and quick installation.


very helpful to find the right brackets


Super fast service exactly what I order ed


Exactly what we expected, good price, and fast shipping. Perfect! Thanks!!!


Item shipped fast (granted I chose the pricier 3 day option). Parts worked great on my 15+ yo Yakima Rocket Box.


Did not fit

You mentioned that it did not fit and I wanted to see if you could explain in more detail what you mean. Did you have the model CTC-18S cargo box.
-- Etrailer Expert Jenny N - 10/14/2022


Easy to use website and quick delivery. That is all I could ask. Thank you.


Great job unable to find those parts anywhere else thank you very much


Although we sold the car top carrier recently, the hydraulic arms were still working. Great product to be able to keep using the original carrier.


Sturdy and fit perfectly


I needed to attach a luggage carrier to the top of my vehicle more securely than just straps around it. After measuring the holes in the car top carrier I ordered this attachment. The pkg arrived on time and was reasonably priced for the strength it provided. While the “u” bracket wasn’t shaped like the rails (rails are flat rather that pointed), the bracket still fit on my 2013 Ford Edge rails. Car top carrier was secure. No whistling and other noise that the straps would have made was heard. I am a female, age 75. I will order from etrailer again.


Worked perfect received them promptly


I had received an 18 cu ft hardshell rooftop carrier free but it had no hardware to attach it to the rails of my car. This kit contained everything needed for attachment and it fit perfectly. Enough stuff can be loaded in this that now we are able to see out of the back window of the SUV, handy with traveling yearly to and from Florida and Massachusetts, and the hardware kit holds it safely.


Works great on my older Thule roof cargo box. Replacement hardware fits my 2018 Subaru Outback roof rack bars. Faster installation with this mounting kit.


Paul B. was very helpful when I had trouble with the web page. He verbally took my order, did a repeat back, I confirmed the order was correct and the order arrived as ordered and on the day he said it would arrive. It was nice to be part of the professional exchange. Thank you!


Worked perfectly for an older Yakima Space Cadet roof box

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