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leaking tonneau cover

dipietro

Full Member
Joined
Feb 20, 2013
Messages
21
Location
boston MA
hi, let me start with a little history.  2011 z71 with 9,500 miles yes nine thousand five hundred. bought it in feb 13 w/ 7000.  got it from a Chevy dealership in RI, still has factory warranty, certified warranty, and GMPP extended warranty. Since i live in Boston I brought it to my local dealership for water leaking into the bed during heavy rain and car wash.  Remedy was cleaned out "water management system.  Go through car wash, it leaks worse than before...back to same dealership. Remedy adjust all panels.  Car wash again, still leaking.  back to dealership. Remedy replace all seals on panels and silicone rubber gaskets.  Car was again still leaking just as bad. Dealership says its adjusted properly and suggest not using the car wash.
  This leaks from every seem, between all three panels, where the front panel meets the rear window, rear panel meets tailgate.  Spoke to a number of AVY owners none of which have experienced any leaking like this.  This isn't a few drips, it puddles inside the bed.  Also had dealership body guy look it over to check for any damage or hidden issues...none found.
  Finally called GM directly explained situation, was assigned a case # waiting to hear back from both Service manager and GM rep.  Has anyone else had trouble like this, is this common?  Any suggestions on this is welcome



 
Water managment system is not just the bed drains under the mat which can become jhammed with debris.. it also includes a two top rail drainage system which catches water entering the bed area along the top edges of the tonneau covers. and channels the water to an intrernal drain.

Check to make use that the  drain rails along the top sides of the bed directly under the covers are not plugged and water channels out of them easily. Also possible the amount of water supplied by the carwash overloads the capacity of the rails to drain in which case it will spill onto the bed.

Also make sure the rails have not been removed or severely warped....improperly stored tonneau covers can warp, split or otherwise deform the passenger side rail.
 
silly as it sounds but have you looked at the bed mat? When I got my AV (from a Chevy truck dealer) I would get puddles in the bed, I was cleaning the bed one day and decided to pull the bed mat out, took a real close look at it, smacked my head and went dang, silly dealership put the bed mat in backwards and covered up all the drain holes in the floor.
 
If its leaking from every seem, then they cant be adjusted properly..  Sounds like when the handles are turned its not bringing the panels tight enough..  Pictures could help to ensure that we dont see something they over-looked.. 
Dont give up, as the bed should be DRY..!!
 
hi thanks for all the advice.  i don't think its so much of a drainage problem as it is a "sealing" issue.  the puddles that that form in the bed are on top of the bed mat.  Picture this...two lines of water directly going across (side to side) the bed below where the panels meet, water running down the midgate (bedside), water running down the tailgate (bedside)  as well water dripping in all four corners. 
  just got off the phone with GM...basically just repeated what the service tech said to her.  got message from the service tech saying as far as they are concerned everything is OK. AND still telling me that i CAN NOT use the car wash.  But yet they claim they have not had any issues like this before with any other AVY...BS. 
  Not sure where to go from here, I'm afraid if I pick up my truck from the dealership they wont ever look at it again and ill be S.O.L.

any more help is greatly welcome. 
 
So if it rains really bad then what? 
The panels aren't supposed to leak.
I have gone through numberous washes over the last 10+ without them leaking.
Still sounds like the striker pads are out of adjustment.
 
Check the Plastic C channel under the rear edge of each panel....
This is where any drips that pass the seal are supposed to go into and then run to either side...

Have you lubed your seals with anything?

I like dielectric grease as it keeps them soft and helps to seal.

 
well spoke with GM again today....according to the local dealership everything is working as it should. So are no longer willing to work on my vehicle.  However the dealership never actually saw it leaking b/c the refused to use any type of high pressure or take it through the car wash like i asked.  That being said GM basically to me to pound sand and to avoid the car wash.  But im welcome to get a second opinion if id like from another dealership,and if that second dealership detects an issue then GM will look into it. 

as far as checking the C channels and such as of right now its still at dealership until tomorrow morning, and the seals were greased when the new ones where installed.  I know this bc silicone and hand prints were all over my rear window, panels and sails. lol 

i will def make mention of the channels, strike plate, locking arms when i bring it to second dealership.

 
You're in Boston so there should be a lot of chevy dealers in the area.  Find out which ones offer a car wash and go there.  Ask them to have one of the lot boys, or another employee,  ride in the back as it goes through the car wash and possibly he can locate the leak.  Body shops sometimes have people in a trunk looking for leaks after a rear end accident as the seams may have not been properly welded.  Be sure and take some lighting with you.

This may sound elementary but are the three numbered panels in the right position? 
 
well picked up my truck today from the dealership...still not fixed mind you. however the service manager finally spoke to me after much discussion with his underlings.  He offered to have a specialist come out and take a look at it (only bc they are coming to look at another vehicle), but either way its gonna get looked at again.

also showed him exactly where leaking was coming from...up to this point i think it he thought it was more of the water management issue than at the seems between the panels and what not. 

so now im waiting to hear from him to bring it back. also spoke with third chevy dealer to get a second opinion and have their techs look it over. 

funny, i just crawled into the bed to double check the panels were in in the correct order....they are.
next move may have to put someone back there as previously suggested.

thanks for all suggestions. 
 
Figured I'd update everyone that has helped me up to this point.  Picked truck up today from dealership, GM engineer looked it over and according to him Water management is working correctly, adjustments are correct and " some " water is expected when going through car wash.  I explained to Service manager, that its not water management i have an issue with.  Its the seams between panels and rear window...and its not "some" water...its lots of water.  even under a normal rain the other day the midgate was dripping. 

so basically they blew some smoke up my A$$ and said see what the second dealership says.  That appointment is Thursday.  stand by for updates

still open to thoughts and suggestions

 
Find a dealership that actually knows their PRODUCTS.
Good luck.
Another member close by that you can try your panels on their av?
Wonder if a person climbed on them and they are slightly wrapped as a result.
Maybe next dealer will allow you to try a new set of panels from another av perhaps? 
 
Take your panels off and inspect the seals. Clean the seals and then lube them, as ygmn says dielectric grease is good. Make sure that the top rails and Plastic C channel at the rear of each panel is clean and clear. When you reinstall each panel set the panel in at a 45 degree angle and push toward the front and then drop it down in place and latch it.

If this fails try another carwash, sometimes if a high pressure jet in a carwash is pointed just right it will blow water by a seal no matter what you do. I know that there is one carwash that I cannot use because it blows water by my sunroof!

Good luck.
 
Don't count on any satisfaction unless you can identify the specific area. After all they have replaced all the seals, verified the drainage system and checked the specific areas of your complaint.......past this they'lll just regard you as a complaining nut.

The previous suggestion that you check panels for warping is a good place to start. In addition, I suggest that you do some work and check the panels yourself so you can identify a specific cause:

On a  bright day, or have someoine use a spot light,  lower the midgate and climb in and see if you can see daylight at any seam
or
Place sheets of paper  along the seam (include the rear window), lock the panel and see if there are areas where the paper can be easily removed identifying a weak area of a seal
or
Dust the seam with a little talc and hit it with water and open to see if there are trails through the powder.

Or, it is possible that the leak is not coming from the panel system at all......water could be getting past the removable rear window seal or perhaps the area where the 3rd light claddding meets the roof and trailing down to the midgate below.

Or, perhaps the dealer has been correct all along and the type of carwash used is to blame.......the drainage system and rear window seal can only handle a certain volume of water.......if you overload that rear midgate/window/#1 panel area with a few inches of static water, or worse a large volume of pressurized water and pressurize air , or park it facing downhill during a heavy rain or after snow melt....it likely will leak.

And, there's a big difference between a leak and a slight drip. I get a slight drip down the midgate below the rear window/#1 panel area and a few drops on the tailgate when I wash my car and flood a large volume of water against the rear window.....so what?......this is in excess of whatever I would encounter in a storm and these are not aquarium seals we are talking about........I imagine that if I placed a large volume of standing water against the rear window and hit it with a blast from my leaf blower (something like you'll get in a carwash) it would leak like a pig. It is also likely the panel seals are good under normal conditions but flex/vibrate when the pressurized air of the carwash is blown against the rear window and across the panel, causing the leak.

Try a different car wash, or better wash it by hand and see if there is any leakage under normal washing and attempt to identify a specific area of leakage using one of the above methods before bringing it in again. Because bringing it in to another dealer for further warranty repair absent and further specifics will probably get you nowhere.....he has accesss to your VIN and all previous warranty work done so unless you have something further, you probably will get smoke blown up your A$$.
 
dipietro said:
Figured I'd update everyone that has helped me up to this point.  Picked truck up today from dealership, GM engineer looked it over and according to him Water management is working correctly, adjustments are correct and " some " water is expected when going through car wash.  I explained to Service manager, that its not water management i have an issue with.  Its the seams between panels and rear window...and its not "some" water...its lots of water.  even under a normal rain the other day the midgate was dripping. 

so basically they blew some smoke up my A$$ and said see what the second dealership says.  That appointment is Thursday.  stand by for updates

still open to thoughts and suggestions
 
so my covers have always had a slight leak between the panels but it was a small enough leak i was ok with it.... yesterday we had what i would call Wyoming's equivalent of a monsoon  :beating: not thinking anything of it i get to work and open the bed to throw some stuff back there and the ENTIRE floor of the bed is soaked .... guess this one is getting bumped up on the priority list  :E:
 
wyotonka said:
so my covers have always had a slight leak between the panels but it was a small enough leak i was ok with it.... yesterday we had what i would call Wyoming's equivalent of a monsoon  :beating: not thinking anything of it i get to work and open the bed to throw some stuff back there and the ENTIRE floor of the bed is soaked .... guess this one is getting bumped up on the priority list  :E:
Hey Wyotonka, old thread, I know, but what did you find and how'd you fix it?

dipietro, did you ever get your issues resolved?  IF so, what'd you find/how'd they fix it?

Thanks,
 
Well, to be honest it's finally normal summer here so rain is pretty sparse. One of those out of sight out of mind type things.
 
Well I did mine today after I notice a leak, clean the drain rails with WD40 and lube the seals with dielectric grease. I found leafs and a lot of dirt and a cladding clip from 2008.
 
MS03 2500 said:
Well I did mine today after I notice a leak, clean the drain rails with WD40 and lube the seals with dielectric grease. I found leafs and a lot of dirt and a cladding clip from 2008.
So did you imprint the date on the clip or something?  :laugh:

I need to try the wd40 or maybe alcohol on my weatherstripping then do something to soften it up.
 
Nope 2008 was when I put the painted upper cladding on.

WD40 did work great.
 
So we managed to take over the "What are you doing today?" thread at Dave's Bar & Grill talking about leaking bed panels so I figured I'd ask a couple more questions here.  I need to fix this by the end of October or I might end up with some unhappy hockey players.  So, the questions are:

  • Is there any benefit over using silicon caulk vs. 3M black weatherstripping cement?  if so, any particular caulk I should use?  I have a fresh tube of the weatherstripping cement
  • My tailgate is not sealing against the back panel.  i can see light through the gap at night if I turn on the bed panel lights.  I don't think it's from the panel being warped, I think it's that the tailgate needs adjustment.  I've seen mention of adjusting the tailgate to get it to close better.  My question is, what do I adjust.  I took a couple pictures tonight for reference

So, do I adjust the round knob towards the top of this picture?

IMG_20140929_201007028.jpg


Or do I adjust the hinge mechanism at the bottom?

IMG_20140929_201016016.jpg


Or do I adjust the locking mechanism in the door itself in this picture?

IMG_20140929_201106771.jpg


Thanks.
 
I would only try to move the tailgate closer unless you think it's out to far otherwise it might not close properly. Most likely he seal has been compressed over the years and needs to be replaced.
 
OK, I think I need to take off and re-seal my weather stripping.  I did verify there is water in the "C" channels which I assume is a good thing.  Here's a couple pictures of the leaks and the weather stripping.  The first picture shows drips on, well I don't really know what this piece on the panel is called but there are water droplets on it:
IMG_20141003_201506360.jpg



IMG_20141003_201537540.jpg


This is the lock down for the number two panel.  The paint has come off but it does move freely after I hit it with silicon in the summer.  I don't know if this could have anything to do with it.

IMG_20141003_202455548.jpg


This is the weather stripping on the panel that's giving me grief - leaking in the middle of the bed.  Since it seems to pull freely and, which you can's see in the picture, there's moisture down in the weather stripping where the sealer is, I assume it needs to be removed, cleaned and re-sealed.  So, going back to my earlier question, is there a reason I should use caulk instead of 3M weatherstripping cement?  If so, what kind of caulk?

IMG_20141003_202650582.jpg
 
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