Bakflip MX4 tonneau - this much leak normal?

[alrashid2]

Thanks Todd!!

It's tough to see where exactly the drips are coming from. Looks like most of it is in fact from the bed rail holes. One spot does seem to be coming from the hinge between the folding covers. Some from the tailgate open area that is inevitable.

I park on a decline, so the water runs towards the bulkhead not the tailgate, so the rails being open there actually doesn't effect me for the most part.

Thanks again all!

Sponsored

 

[Geo8866]

Oh wow, can you elaborate on that? Not picturing what you mean

I'm not sure how clear this pic is but in the front, by the cab there was a space where at least some of the water was coming in . I filled the area with sealant and it definitely helped.

 

[alrashid2]

Hey guys, got to looking a bit more and realized that, other than the bed rail leaks which are not the tonneau's fault, the right half of the first folding seam is also leaking... Water is dripping from somewhere at the folding seam on the bottom side, and the bed directly under that is also wet. I tested this in my usually parking spot which faces downhill but is level from left to right, and also parked flat. Definitely leaking from the seam.

Anyone seen this before? And is this something I can re-seal myself somehow? The drivers side of the seam stays dry, and all of the other seams are dry too.

@RealTruck sorry to keep calling you out again but wanted to get your take too. Thanks for the help all!

 

[RealTruck]

Hey guys, got to looking a bit more and realized that, other than the bed rail leaks which are not the tonneau's fault, the right half of the first folding seam is also leaking... Water is dripping from somewhere at the folding seam on the bottom side, and the bed directly under that is also wet. I tested this in my usually parking spot which faces downhill but is level from left to right, and also parked flat. Definitely leaking from the seam.

Anyone seen this before? And is this something I can re-seal myself somehow? The drivers side of the seam stays dry, and all of the other seams are dry too.

@RealTruck sorry to keep calling you out again but wanted to get your take too. Thanks for the help all!

Always glad to be of assistance!

The MX4 Gen 3 comes with an industry leading 5-year warranty. If you're ever having issues with your cover, we're here to help! I've DM'd you so that we can take a closer look.

 

[alrashid2]

I've got an update to the water test! It is actually not leaking from the seams... but it is still unfortunately the tonneau cover.

I first covered all of the bed rail take pocket caps with plastic and taped down to minimize any leaks there so I could better decipher where the leaks were coming from.

The Sources:

1. Randomly leaking at the back two corners closest to the bulkhead (PHOTO 1). It was leaking from somewhere on the tonneau cover that I couldn't quite tell, then dripping onto the drain hoses and down those. That one I can honestly live with it since it's at the back corners where it should drain out the bed anyway...

2. Leaking between the rail and bed rail covers (PHOTO 2). This one shocked me but I was able to completely confirm it. There is a very thin foam gasket where the rails meet the bed, but apparently it isn't enough. It seemed most prevalent where the bed rail cannot fully be flush against the bed rail covers, as they have raised areas. The leaks were mostly coming from where there was a gap between the raised areas and the water was making it's way through the gap, and down into the bed behind the rails. Only thing I can think to do here is uninstall the rails, and find a thicker foam gasket tape to put onto the rail and compress that as I reinstall...

In the photo I tried to outline how it is leaking with a photo from the end of the rail. Just to be clear, it is NOT leaking at the end of the rail but across the entire rail at various sections. Photo just to help illustrate it.



3. Actually leaking past the rubber seal on the top of the rail where the rail meets the tonneau cover panel when closed (PHOTOs 3 and 4). This was the most shocking. If you look inside when the tonneau is shut, the panel does not sit tight at the hinges against that rubber seal. As a result, when a lot of water goes into the rail drains it seems to exit out this opening at each seal instead of staying sealed and moving down the drains. This is what made me originally think it was the seams themselves leaking when it actually is not: the water is just running out that hinge opening, hitting the seams and latches, and running down those. Unfortunately this one seems just like a design flaw rather than a defect in my cover specifically. Also seems like it would only be an issue during heavy rain when the drain rails can't keep up. Think like a small gutter during a big storm overflows: it's overflowing out the gap.

So that is where I'm at. Leak 1 (near bulkhead) seems minor and I can live with. Leak 2 (between bedrail covers) I may be able to fix myself if I can find the right foam gasket tape. But Leak 3 unfortunately seems inevitable.

I think my fix will be to focus on Leak 2 and uninstall the rails (again), get some proper foam gasket tape and seal where the rails meet the bed, and reinstall.

 

[mattmico]

Hey guys. Have the Bakflip MX4 tonneau. Downpoured all day today. Checked today and got this much water in the back...

Looks like most of it is coming from the bed rail caps. But definitely some leaking at seams and such.

Im ok with it as it really is only leaking at the edges of the bed and draining along the side. Middle is dry.

Just wanted to make sure this was normal. Thanks all

Hey guys. Have the Bakflip MX4 tonneau. Downpoured all day today. Checked today and got this much water in the back...

Looks like most of it is coming from the bed rail caps. But definitely some leaking at seams and such.

Im ok with it as it really is only leaking at the edges of the bed and draining along the side. Middle is dry.

Just wanted to make sure this was normal. Thanks all

I also have the same cover. I did not install the drain tubes and I get about the same amount of leakage as you’ve pictured from an automatic car wash.

Sponsored