Can I Use the TrailSeal Tailgate Gasket- A Tight Tailgate Seal with My Tonneau Cover?

Updated 01/22/2026 | Published 01/20/2026

Question:

Can this also be used as a seal between the end of a tonneau cover and the tailgate top?

asked by: Jim

Expert Reply:

Hello Jim,

Welcome to etailer, we are happy you found us!

Yes, the TrailSeal Tailgate Gasket- A Tight Tailgate Seal # 834532001583 can also be used to help seal the gap between the end of a tonneau cover and the top of the tailgate. It’s a common fix for reducing dust, water, and debris that can sneak into the bed through that area.

The TrailSeal is designed to seal the gaps around the tailgate, which is often the weak spot even when a tonneau cover is installed. Since it’s cut to fit and has strong 3M adhesive backing, you can trim it to work right where the cover meets the tailgate. It works well with both soft and hard tonneau covers.

As long as the surface is clean before installation, it does a great job improving the seal at the tailgate.

What brand tonneau cover do you have, and how do you like it?

expert reply by: Kate F

Jim

1/21/2026

Hi Kate, thanks for the reply, just what I needed. I have an undercover ultra flex hard folding cover. The seal has failed on the end of the cover--not sticking--and I'm getting a lot of water in the bed. It was installed in cold months and I'm sure that has a lot to do with it sticking to the cover. Its a nice heavy cover, locks down really well but the seals all the way around could use some work. I'm going to go ahead and order the TrailSeal but probably won't install it until the weather warms up. Just to be sure the kit includes enough seal to go all the way around the tailgate to include the top of the tailgate? Does the top seal adhere to the tailgate or the tonneau cover?

Kate F.

1/21/2026

@Jim The kit includes enough material (9 1/2') to cover that area, and you can cut it to fit just the top edge or continue down the sides if needed. For that top section, the TrailSeal # 834532001583 will adhere to the truck itself, top of the tailgate, not to the tonneau cover. When the tailgate and cover are closed, the cover presses against the seal to close off that gap and keep dust and moisture out. Waiting until warmer weather is a good call, too. The adhesive bonds much better when it’s warm and clean, so installing it then will give the best long-term results. I would like to mention that you could always reach out to the manufacturer of the tonneau cover to get the replacement strip for that cover.

Doug

1/22/2026

@Jim I do a bit of driving on dusty logging roads. I have no experience with the Trail seal between my soft top and tailgate as there is no need for it there.However I get dust from the gaps between the tailgate and sides and bottom of cargo box. I had to remove the seal from bottom of tailgate and cargo box as it collects dirt and moisture. So recommend you not use seal for base of tailgate.

Paul

1/22/2026

I have an ARE topper on my GMC Canyon. Every time I ran through the car wash, water would end up inside on the bed liner. I had used the Trail Seal tailgate gasket on my truck tailgate to eliminate dust infiltration. It worked so well that I ordered more and placed it along the top and down the sides of my topper flip-up door which eliminated water entry. I did not remove the original gasket as there was enough space to place the Trail Seal gasket just outside the original gasket. I highly recommend it.

Kate F.

1/22/2026

@Paul Thanks for the response Paul, I am happy to hear this worked out so well for you.

Kate F.

1/22/2026

@Paul Thanks for the response Paul, I am happy to hear this worked out so well for you!

Mike

1/22/2026

I only used Trailseal on the tailgate of my F150. It worked well there and stopped the majority of dust when I drive on dirt roads. As noted, the trick is to have a clean surface for it to bond onto. The adhesion is excellent if the surface is clean. You also need to use some imagination in corners to fill the odd little gaps near the hinge and latches. I tried using it on my topper, but found it was too thick and the topper didn't seat evenly.