Weatherproofing the Bed

People must be extra OCD then. I only put weather stripping on my tailgate and have never had any problems

 

Exactly. The only gaps the 3rd Gen really has are the header rail and TG. Some might seal under the rail caps if being thorough. This completely ignores the crazy leakes that the OEM tonneau has.

The Rok Block kit that I paid about $10 less than shown in the box below fixed most of it. I still haven't hit the header rail gaps yet. Someday, when I'm bored.

 

So the general consensus is the most important places to seal are the gaps in the top front corners of the bed where all the bed rails meet and the tailgate (which I already have sealed). Would it be over kill to seal under the plastic bed rail covers?

 

Sorry to say, but there's lots of wrong information on this thread.

The bed-sides & tailgate caps, side rails, and bed-front structural bar are the areas where a majority of water infiltration is taking place. Next is the gap between the end of the bed and the tailgate, followed by the upper & lower corners where the bed and vertical bars meet. Also, at the top, right in front of the tail/brake lights, there's a nice gap that runs horizontally and vertically. Oh, and the storage boxes in the bed, as well.

There's a really great thread on this very same issue, years in the making, with very good information. I'll find it, and paste into this thread.

In the meantime, look at the link I posted (and copied here, on page 1) so that you can see why waterproofing the bed is so difficult (hint, it's because the bed box, rails, caps, corners, etc. are 18 separate pieces that Toyota didn't bother to seal.)

 

Only if you see water coming in there. The only water / dust that I have seen is the front corners and TG bottom gaps.

I bought foil tape and caulk to hit them before I get a topper. Not motivated enough at this point.

 

I must not be using the right words when I search because I can’t find anything using the search bar

What did you do exactly besides your bed rails?

 

I got small strip of adhesive foam from Amazon for the side rails. Put this on the rails and re-installed them.
Then I grabbed some RTV sealant, which I'm going to cover any openings in the cover where the seams meet.
Got a tailgate weather seal kit for the rear.

For the nooks and crannies I used this foam.


Cut the outline and stacked it. Took off the rails and stuck it in and pressed it down to fit.

 

The search function is wonky; let me see if I saved the thread.

The truck bed is a set of jigsaw pieces that aren't all directly attached to each other--and not any are sealed.
All of the pieces have to be sealed together to form ONE unit--if you're going to have any hope of keeping out water & dust.

Starting at the plastic bed, you have to remove everything attached to it: the side slide rails and top caps, the front header bar (with front header slide rail, if you have one) and working towards the tailgate, remove the tailgate top cap. When you remove those pieces you begin to see the myriad of places & ways that water & dust get in.

Water & dust & dirt typically get blown up from the ground in between the cab & front of the bed; the wind forces water & dust/dirt under the front header rail, straight down into the bed &/or along the length and then into the bed by way of the side gaps in the front.

Another way is underneath the top caps of the bed walls; there are approx a dozen holes cut into the top of the sheetmetal on each side, and the top caps wedge themselves using those holes. Looking down into the holes, you see the ground--so as you're driving, all of the road dirt is being shoved up into those holes, and into the bed. Same for the holes in the storage compartments in the bed. Same for the large gap at the end of the bed, between the tailgate.

I used the Eternabond Putty Tape, and made an adhesive & barrier seal between all of the individual parts. I ran the Eternabond the entire length and width of the tops of the bed walls; from the top outside edges of the bed, down into the bed, right below the nuts for the slide rail bolts. Each strip of Eternabond, is overlapped by 1/8" over the next lower strip, until I was approx 1/8" below slide rails. This goes all the way back to the tailgate. At the front of the bed, between the front header rail and side caps, there's a gap approx 1/3" - 1/2" --to fill that space, I folded the putty tape into a wedge that fit in tightly.

I did the same for the tailgate cap, except that I also ran a bead of silicone caulk underneath, because there's a ridge where two pieces of sheetmetal are riveted together. To seal the tailgate gap, I added the ESI Ultimate Tailgate Seal with Taper Seal.

I'm sure that I'm forgetting something... but that's pretty much it.

Ask if you have more questions.

 

I tried that sealant, and some minimally expanding foam... they both got all over the place, but neither would stay where I wanted them.

I received my A.R.E. camper shell yesterday, and an afternoon rain showed me that I'm dry everywhere I put down the putty tape. I still have some water penetration happening at the top rear of the bed, where the opening of the shell and the bed meet. That may be where I squirt a small bit of the expanding foam; let it cure, then shave it down for a tight fit.

I looked at the window seals, and they look like they're making good contact with the window. I'll sit it the bed and let a friend spray a garden hose along the window edges, to see if they're leaky.

 

That’s some good info, thanks

 

This helped me a lot

https://m.youtube.com/watch?v=LIWht8rxbW8

 

I just some pieces of black flex seal tape and covered those bed holes.

 

Sweet I got some of that EsI stripping. Exactly what I was looking for. Hope it takes care of the majority of water. I’m not looking for it to be completely water tight. I think I’m at the point where a few drops of water here and there will be fine