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Leaky 3rd Bed Cover/tailgate And TSB 02-08-66-002?


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Mar 10, 2002
Vancouver, WA
Alright. ?I hope this hasn't been discussed before. ?I did put in an hour or two looking for similar posts, but didn't find anything. ?So forgive me if this has been covered already.

Couple weeks ago, my wife and I noticed a "whistle" when driving @ 40mph with the midgate down, tailgate closed, and all bed covers in place. ?Sure enough, it stopped when we stopped; whirred right up when we got going again. ?I wondered if we had an air leak somewhere. ?When we got home, I parked it in the garage, crawled in the bed, and my wife ran a flashlight down all the seals: between each bed cover, between bed covers and side rails, and between the last bed cover and the tail gate. ?Voila! ?at the driver's side rear corner, it was visible that the gasket on the last panel had pulled away from the tailgate an 1/32" or so.

Pretty confident this was the source of the whistle, I took it to the dealer. ?My service writer went along with me and we "duplicated" the problem. ?She screwed up her face and admitted that shouldn't be. ?Whew. ?Good. ?The "service dudes" drove it around with the midgate down and with it up, and returned it saying that it was "normal--that 'air turbulence' is to be expected."

NOT! ?I told the service writer that couldn't be normal, 'cause it didn't do that when it was new. ?Worse, what happens when it rains.... (yeah, yeah, push the rain and water leak issue, yeah...) ?She admitted that could be a problem and scheduled another appointment for Tuesday (7/30) for a "leak test".

So I dropped it off yesterday and they had it two days. ?Curious, I called the service writer and casually asked what the status was. ?She apologized for not calling me sooner, but said that they had found TSB 02-08-66-002 regarding "water leaks at endgate" and had sent my truck to the body shop for the appropriate repairs. ?The body shop guys could have it for another couple days (gasp!) and she would call me as soon as it was ready.

Okay, well, I guess I should be glad that they are at least doing something. ?Or at least pretending to. ?But my question for the club is "Has anyone heard of this TSB and what does it really mean?" ?This link

2002 Avalanche - Structure Body

on Edmunds gives the scant description that the service writer gave me, but I have yet to find additional details.

BTW, I ran my own "leak test" before taking it in. ?I got the hose and thoroughly doused the rear corner of the tailgate/bedcover area where the gasket is pulling away from the tailgate, and let the water "go where it wanted". ?A few minutes later, I dried off the top (so no pooled water would run in) and opened the tailgate. ?Yup--a nice pool of water on the rear left side about 4"x4" in size. ?I dried it off, did the test again, and crawled inside the bed (from the inside). ?I found the water running down the tailgate and pooling in the same place. ?I'm fairly confident this is the source of the dry-weather air whistle too.

I'm just wondering what the body shop is doing to my truck for two days. ?Has anyone had this problem, and had this TSB # come up?

Thanks in advance, and I'll update this thread once I get my truck back.


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After a couple of problems I don't trust the service advisors. I really wonder about a problem of this sort where they have the vehicle for 4 days. Better look it over close when you get it back, maybe the trip to the body shop is to repair a dealer caused dent or scratch. Did they give you a loaner for the time they have the truck, or are you "on your own"?
IS the TSB where they sand the tailgate smooth so the seal will sit better?

I remember that one somewhere on here.....

Good Luck
the body shop visit sounds a little fishy ...... i also have a little leak between the 3rd panel and the tailgate. i think mine i caused a bad seal. the seal on the panel is bowed down and water collects there and then leaks in. i havent taken mine in cuz it hasnt rained near denver in about 2 months :cry:
I like the edmunds link to tsb descriptions. I've had mine a few weeks and have noticed some water in the bed area. Didn't know if I'de assembled things incorrectly or what. I also get water dripping from the rear window where water pools.
haven't had time to go back to the dealer.
Well, I'm not into conspiracies, so I doubt the body shop trip is to "cover up something". I don't know how everyone else's dealer service departments are set up, but mine has an onsite body shop. This is where, for example, they fixed the rust problem under the door seals caused by the roof rack installation. Obviously, they had to sand down the old paint and rust, and repaint it--that was done in the body shop.

Anyway, for this leak problem, I'm calling over there right now before they start "modifying" stuff to find out what problem/solution they've come up with.

Just got off the phone with the guy in the body shop. The "procedure" they followed was to sand off the roughness of the tailgate and repaint it. Presumably, this "rough" texture (I'm guessing this new Protec tailgate surface) doesn't seal up with the rubber gasket on the last bed cover, and thus, water leaks in. Sheesh. I'm a little nervous as to what it looks like and how stable of a fix this is going to be. I have to wait until tomorrow morning to pick it up (the paint has to dry overnight), so we'll see.

Darn. And now I'm wishing I had taken some "before" pictures. If anyone's interested, I'll take some "after" pictures. I just hope it doesn't look goofy. ygmn, I guess you win the prize for guessing it correctly. So am I the only one on here to have this done?


I'd like to see some pics after you get it back. I'm sure it'll look fine.

I had mine in for a leak between panels 2 and three, just above the puddle in the bed. They didn't find a leak there, but pulled out the TSB you referred to. The TSB called for just what you said, but they didn't have the materiels to fix the tailgate after they sanded it down -- it would take a few days to get it.

Funny, it didn't leak there before.

Anyhow, I'm still waiting for the call back to get it "fixed". That was in April. I've not noticed a leak since.
brmiller said:
?ygmn, I guess you win the prize for guessing it correctly.


But you said you had a gap....sanding would make the gap larger right?
atgr said:
Did they give you a loaner for the time they have the truck, or are you "on your own"?

Oh yeah--they gave me a looser loaner alright--a 2000 Chevy Metro. Gack! This thing is driving me crazy. I didn't really need a rental car (have other vehicles), but I figured, "Since they're offering..." They were out of loaners when I dropped the Av off, so they took me home and brought this can later in the day. Ugghh.. My wife doesn't think it's so bad, but I can't handle it. I'm not driving that thing anymore--the last 3 days have been awful driving experiences. Back to my trusty Nissan 240SX... Gee, what are torque and acceleration?

Well, I got my Av back today. I'm not sure I'm impressed or not. The job they did (see pictures below) is fairly "integrated" into the natural tailgate texture. That is, if it had come this way originally, I wouldn't have known/noticed. As to whether it fixed the problem I reported, or any problem, for that matter, is yet to be determined.

It seems to whistle less than before, but still a little bit; I'll have to drive around a bit more with the midgate down to decide whether I'm happy with it. The Av needs to be washed (or if we get the forecasted showers, I'll wait, watch, and see), so soon I'll have my own leak test and find out if it leaks. If it leaks, I don't have to deal with the whistle issue--that's too subjective anyway. Otherwise, we'll just wait for winter and the Great Rains.

So, here's what my tailgate looks like now. The lines on the [new] smooth section are scratches from the rubber seal on the third bed cover because I think they shut it before the material dried. I'll have to talk to them about this next time I'm there for "other" stuff... <sigh> (BTW, my tailgate is dirty, so forgive some of the "dustiness"--shows I've been hauling stuff...)

And one more thing--the rubber seal on the rear of the third bed cover does make complete contact with the tailgate all the way across. It did, as you recall, separate from the tailgate on the driver's side a bit--this is where I reproduced my problem using a flashlight and a bucket of water. So I think they did more than sand down the tailgate--they must have fidgeted with that seal.

Let me know what you think about this "solution".

The line looks crappy....IMO

I bet they adjusted the covers so it seals in the rear more too.
Are you saying that there is a way to adjust the covers so that they seal differently / better? If so, I'de like to know, i get some water between two and three and sometimes at the gate.
I think if you look underneath you will see that the side mounting thingys have slotted holes.....

I will look again tomorow.
I think it looks pretty decent, and I'd accept it... but what are those lines running lenghtwise down the sanded section. Is that a scratch or dust or something?
brmiller said:
The lines on the [new] smooth section are scratches from the rubber seal on the third bed cover because I think they shut it before the material dried.

Yeah, I think they are scratches of some sort. They lne up right where the tailgate meets the bed cover seal.

I had the leak at the 3rd panel where it meet the tailgate made of Structural Reaction Injection Molded (SRIM).  I considered the TSB to sand, but could not see how this would fix the problem.  (My problem - gap between tailgate and # 3 bed panel.)  I have already messed around with the tailgate latches to move the tailgate in as far as possible.  I described the problem and the dealer ordered a new # 3 bed panel seal where it meets the tailgate.  It appears to be fixed, I have a tight seal in that area again.  Time will tell.

Per my service report-

Part #:  88944067  Description: Seal 17.090

:wave: Yes I have had that problem they replaced the 3rd Bed Cover the first time now that it is out of normal warranty they say what problem. IF you take a yard stick and lay it across the cover I would bet there is a bow in it also. Good luck the Bow will get worse and the corners will pull up away from the tailgate.
The third lid on my 2002 is warped also and there is a small leak into the cargo bed at the corner of the tailgate.
I hope they improve on the flimsy rubber channels that carry away water that gets under the bed covers, mine cracked the first time i tied off a large piece of cargo to the side of the bed. I've repaired it with silicone, but it does not hold.