Discussion regarding T6 ONLY roof corrosion

Some body shops have already tried this but they were told not to continue because it was not part of the VW Approved system.
There is also a photo on here somewhere of bubbling under the tape.
 
Regrettably it is our problem. It's the owner that suffers the interminable wait and frustration for what turns out to be a 'temporary' fix. VW don't really care about a problem affecting a very small percentage of their customers who in the end go back for more punishment because of lack of competition.

We fix other shortcomings by using items such as the bungee and spare wheel safelock so if the tape permanently ends the corrosion issue why not?? I would go for it if it is a reasonable price for the peace of mind and to terminate this thread!!!!!!
 
Some body shops have already tried this but they were told not to continue because it was not part of the VW Approved system.
There is also a photo on here somewhere of bubbling under the tape.

If the tape was properly applied such that it completely isolated the seal from the roof and the corrosion re-appeared, then the seal is not the problem.
 
But surely the tape would need to be applied at manafacture as the problem starts as soon as the rubber seal is attached so there would not really be any benefit. Also once people try fixing it themselves VW will care even less about the situation.
 
If the tape was properly applied such that it completely isolated the seal from the roof and the corrosion re-appeared, then the seal is not the problem.

I agree, it must be something in the aluminium or the paint or a reaction between the two.
All you have to do is convince VW which aint gonna happen.

Remember VW are invincible and we are scum:thumb

Although we do actually pay their wages.
 
I have an early T6 Beach Dec 15 - never seen a garage with 30k miles of hard use - and at the moment i have no issues to report - i have a non-metallic paint finish on mine and wonder if anyone has suffered the problem with a flat colour ?? white red or yellow ?? maybe the paint problems are compounded by the metal in the metallic paint and maybe the boring colours are the better at resisting the corrosion options - just asking
 
I've had a look at mine after a shower of rain. Most of the seal is, well sealed but there are places where it is not and in these places the seal is holding the water. I suspect that removing the seal would not help matters so for the moment I have not done so.
In respect of tape around the edges I can see that this would offer some protection from reaction with any metal in the seal but it would not stop the water sitting there.
My guess is that the best option would be to firstly to use a seal that had no metal in it and to ensure that this seal was in fact a seal and not allowing water penetration.
I therefore do not yet know if I have a problem or not but it seems pretty certain that I will.
Our stumbling block seems to be a proper investigation by VW. Our point of contact is through the dealers but as they are not ultimately responsible for any repair it is hardly surprising that they will not undertake any investigation or authorise any preventative action. We therefore need to be talking to someone senior at VW UK. Our only leverage with them is publicity. If I was a senior member of VW management I would not want to be responsible for a rally outside my offices with the press in attendance.
So far some have removed the seal and found a problem and some have not. Some don't want to look as they prefer to leave the discovery closer to the end of the warranty period, some prefer not to know, some don't think it's a big issue and others like me are reluctant to do anything that might invalidate the warranty or make matters worse. It therefore becomes very easy for us to appear disunited on the issue and I can see how those who have looked and found a problem are frustrated by those who haven't.
Our issue is with VW, not our dealers, not the repairers and certainly not with each other.
I am therefore in a position where I don't have a problem that I know about but it takes the edge off ownership knowing it's more than likely going to occur. I prefer to be proactive and prevent the problem with a fix, rather than reactive and fix the problem. So what the hell are we going to do about as I suspect I am not alone.
If something is being done in the background by all means let me know by PM and delete this post.



Mike
 
I have an early T6 Beach Dec 15 - never seen a garage with 30k miles of hard use - and at the moment i have no issues to report - i have a non-metallic paint finish on mine and wonder if anyone has suffered the problem with a flat colour ?? white red or yellow ?? maybe the paint problems are compounded by the metal in the metallic paint and maybe the boring colours are the better at resisting the corrosion options - just asking

Have actually looked under the seal?
 
Shoot me down if this is a stupid suggestion but would it not be possible and beneficial to apply a transparent flexible tape to cover the edge of the roof that is in contact with the seal? The tape would be a few mm proud of the seal and would not be visible being transparent. I have no idea how possible it would be to obtain such a tape but I am sure someone here would know.
If the tape prevented the area of roof paint under the seal being submerged in water I think it may be a solution. Tape would have to be 100 percent water tight inside and out of the roof to be effective. I think the silicon grease would do the same job. The more I get to know the more I am convinced the water that sits in the seal is the biggest cause of this roof corrosion issue.
 
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If the tape prevented the area of roof paint under the seal being submerged in water I think it may be a solution. Tape would have to be 100 percent water tight inside and out of the roof to be effective. I think the silicon grease would do the same job. The more I get to know the more I am convinced the water that sits in the seal is the biggest cause of this roof corrosion issue.
I was thinking of vinyl wrap material like 3M venture shield that the front of my cali is wrapped in.
 
The more I get to know the more I am convinced the water that sits in the seal is the biggest cause of this roof corrosion issue.
Water is the catalyst. The cause is the two dissimilar metals, aluminium and steel in close contact that causes the issue. Water on aluminium itself isn't enough. The real culprit is the steel protruding through the seal. Without this the corrosion wouldn't occur. AFAIAA of course
 
Water is the catalyst. The cause is the two dissimilar metals, aluminium and steel in close contact that causes the issue. Water on aluminium itself isn't enough. The real culprit is the steel protruding through the seal. Without this the corrosion wouldn't occur. AFAIAA of course

I agree but without the water I believe the corrosion would not occur, the front of the elevation roof has the same metal insert seal but different shape, because the front seal does not allow water to sit in the seal due to being horizontal, the front edge of the roof does not have the same problem (on my van anyway).
 
Water is the catalyst. The cause is the two dissimilar metals, aluminium and steel in close contact that causes the issue. Water on aluminium itself isn't enough. The real culprit is the steel protruding through the seal. Without this the corrosion wouldn't occur. AFAIAA of course
Agree, but the blistering may still occur as a result of the simple prolonged submersion of the paint in water.
 
Maybe OT here in this T6 thread, but that was exactly the opinion of our dealer Campercentrum in Amersfoort (NL), who repaired our T5.1 (2009) roof two years ago. It's water ingress between the alu roof and the rubber sealing, together with dirt and sand underneath, that "sands" the laquer, and leads to electro-chemical blisters, he told us.

Against the new rules of VW Hannover he taped our roof around the the edges, inside and outside, under the rubber.

VW had forbidden this practice, demanding that the roof should be sealed against water by glueing the rubber seal tight on the aluminum edges.

Glueing does not prevent the sanding of the lacquer against the rubber, says our dealer.

Time will tell.

In the mean time we keep smiling every day we're on the road with our wonderful travel capsule.

Blisterfree greetings from Amsterdam,

Marc.
 
Maybe OT here in this T6 thread, but that was exactly the opinion of our dealer Campercentrum in Amersfoort (NL), who repaired our T5.1 (2009) roof two years ago. It's water ingress between the alu roof and the rubber sealing, together with dirt and sand underneath, that "sands" the laquer, and leads to electro-chemical blisters, he told us.

Against the new rules of VW Hannover he taped our roof around the the edges, inside and outside, under the rubber.

VW had forbidden this practice, demanding that the roof should be sealed against water by glueing the rubber seal tight on the aluminum edges.

Glueing does not prevent the sanding of the lacquer against the rubber, says our dealer.

Time will tell.

In the mean time we keep smiling every day we're on the road with our wonderful travel capsule.

Blisterfree greetings from Amsterdam,

Marc.

Hi,

Thanks for sharing that with us, do you ever remove the seal to check underneath?
 
Mine was repainted last two weeks in July and 6 weeks later it had massive bubbles. No time for any sanding effect IMO.
 
I would be very interested to see an independent bodywork specialist's report on what the has caused the corrosion.

And I'm sorry but the sanding effect sounds like typical VW BS. If the roof rubs around that much in the seal you would be able to see the rub marks. Some folks have shown lines on their roofs but not rub marks.
 
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Raptor U Pol is a paint which can be applied below the area of the seal trim and can be over painted. Earlier suggestion was found by someone to be funny but it works as a tough barrier in the load area of pick ups. It is extremely tough and would create a barrier between the seal and the roof. If my Ocean ever shows sign of bubble I would ask VW to consider its use. Better to be positive than negative as I love my California.
 
Hi,

Thanks for sharing that with us, do you ever remove the seal to check underneath?

It's tempting to have a peek under the seal, but I ask our dealer to have a look at it, when the van is there for MOT next month. Don't want to damage things.

Marc.
 
I would be very interested to see an independent bodywork specialist's report on what the has caused the corrosion.

And I'm sorry but the sanding effect sounds like typical VW BS. If the roof rubs around that much in the seal you would be able to see the rub marks. Some folks have shown lines on their roofs but not rub marks.

My dealer says the first cause is water under the rubber seal. Sanding comes second. Maybe I didn't express myself clear.

Marc.
 
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