Seal bed rail caps

I agree that you want a flexible material instead of rigid. I do not know what I actually bought, but I went to Home Depot and read labels. I chose a clear, flexible, ok for metal option.
I squirted it on, and replaced the caps within a few mins to make sure they would still go on easily.

 

Hadn't even considered the RV stuff!

 

I've got a tube of this stuff waiting for when I get ambitious enough to remove my cap:

http://www.tremcosealants.com/products/acoustical-curtainwall-sealant.aspx

It never fully hardens so it seems like it should work well in this application. Beware that this stuff is known as "black death" in the construction industry due to it's tendency to get all over you (at least when you're using it to seal seams in a poly vapor barrier in a crawl space).

The rail caps will leak if you like to hose off the underside of your truck in the winter to remove road salt.

 

Well I just sealed most of my rail caps with Geocel Proflex. During the process of removing the plastic rail caps, I found that there was more of a gap at the front corner than was visible with the rail caps in place. There's actually about an inch gap between the plastic rail cap and the metal side rails, and the plastic portion of the bed behind the cab. Has anyone tried sealing this gap with a foam sealant like "Great Stuff"? I don't even know if the caulk style sealant would fill a gap so large. Thanks.

 

Put down the spray foam, and step away from your truck! Get some butyl tape for those big gaps.

$16 XFasten Butyl Sealing Tape, Black, 1/8-In x 3/4-In x 30-Foot Plumbers Putty Tape, RV Sealant Tape, Butyl Rubber for Boat Sealing, EDPM Butyl Tape RV

https://www.amazon.com/XFasten-8-In...969009&sr=1-1-spons&keywords=butyl+tape&psc=1

 

Sounds like a good plan, I will get some of this. Thanks.

 

Here's what I did.... I removed the plastic caps....this left a bunch of holes in the bed side panels...I took double sided tape the width of the panel and applied it, I also did this at the front bulkhead. I then fabricated 1/4" mahogany strips that conform to the curves & taper of the side panels. Routed out spaces on the inside so I could put S/S tabs behind the track rail inside the bed to secure it, along with the double sided tape. At the front bulkhead I cut dovetail joints so the side pieces could be joined to the front piece on the bulkhead.....This created a perfect flat surface on 3 sides, top & bottom.....I installed the cap....no leaks with nothing more than the standard double sided tape....I am not convinced that unless these 3 sections of panels are even with each other from the start, that any type of filler, gook, foam with stop or prevent leaks....I agree what I did might seem over the top, but its the right and only way to get a positive result....

 

any chance you might have a picture or two of this process? thanks

 

I never took pictures and now with the cap on, everything is covered....Another option is to buy the bed caps from KB Voodoo, listed here as a vendor on this forum. Remove the OEM plastic caps, get wide double sided tape, installed between the bed & the steel caps from Voodoo. They do not make a cap for the front bulkhead, but a 1/8" of flat stock will take care of that....Whether you use oak, mahogany, steel, or aluminum, the result is basically the same. The culprit for the water leaks are the OEM plastic caps, as they are nearly impossible to seal, get rid of them......

 

got it; thanks for the input.

 

I just got a used Leer 100XQ for my 2017 DCSB. Had a pretty nasty rain storm on my 6 hour drive home from picking it up, and noticed the nasty leak at the front corners of the bed. This is a ridiculous design flaw that is now extremely annoying.
I have searched high and low and this thread, although old, is exactly what I'm looking for. My topper is getting painted later this week, and then I'll be working on getting it all sealed up, and my platform built and the family can get to camping!

 

They do make a rubber filler for those two spots, they are there on trucks that have the OEM Tri-fold bed cover.

The part numbers are:
62541-04010
62542-04010

 

Delayed reply, but thank you for the info! I'll have some flex seal to clean out of the gap, if I get these.

 

Tagged

 

My shop was cool enough to inform me on it and offered to seal it up with caulk.

 

This has been most informative. Will be sealing it up tomorrow.