Water intrusion in truck bed?

I'm going to be installing a shell on my 2021 CM and want to try and keep water out of the bed since I plan on building a bit of a camping platform back there.

Wondering what needs to be sealed up. Plan to seal the 4 holes (two on each side) and the seams between the front and sides of the bed.

Do the plastic gromet doohickies need to be sealed? Looks like they have small holes near the bottom.

BTW, I ordered a Snugtop Super Sport 8 weeks ago and the dealer still has no idea when it will be delivered. These used to be manufactured right here in Long Beach, but now all Snugs are made in Mexico, down by Acapulco.

PS. Spotted this beautiful Cavalry Blue CM with the Snug Super Sport today while out and about. Someday...

 

I would not worry about it

 

My truck has had a tonneau cover on since basically brand new in 2012. There has never been a single drop of water in the bed of my truck in any weather conditions that I have ever been in, and that is not an exaggeration for internet points. I would also say don't worry about it as long as you get a good seal all the way around between the top rails and the cap.

 

My 2021 leaks. I’ve sealed the seam and it still leaks in places. But I don’t worry about it. Open the hatches and let it dry.

 

Before you chase things that don’t leak, put it on then spray it with a hose to see where it’ll leak. I have an ARE cap and it doesn’t leak.

 

I wouldn’t bother with it. I sleep in my bed a fair bit and it’s never an issue. I only ever see water get in under my bed caps is when I deep clean the truck. That includes blasting a hose inside the bed sides to clean above the wheel arches. Dust is another story but you’ll never stop that.

 

The holes near the top don’t leak on mine but the ones low down did so I put some silicone on them. Be sure to use good foam to seal the shell on the rails. My front end was lower than the sides so I used a thicker foam for that section

 

I am fairly sure that the quality of the rail to cap seal that you use is what makes the difference between leaks or not.
I like the dual bulb rubber weatherstrip vs the cheap foam that most dealers will use just to save money and it is not tough to imagine the difference if you just look and see them.

 

I completely agree that you’ll never stop all dust, but I got one of these kits and it did reduce it a lot. Got to look for gaps at night with a light.

https://www.amazon.com/Best-Sellers-Truck-Tailgate-Seals/zgbs/automotive/381760011

 

Thanks all for the advice. Not expecting leaks, but thought this might be a good time to seal before the shell goes on. The shell on my 2005 Tundra does leak at the windows and at the cab seal, not a lot but enough to get the shell headliner wet.

I have the tailgate seal and will install that when the shell goes on. Good idea to look at night with a light.