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Chrome Bumper on 2004 Toyota Tundra Corroding

3 Months ago I purchased a 2004 Toyota Tundra and have recently noticed rust/corrosion spots on my chrome bumper. The dealership is claiming it to be corrosion due to surface debris (salt), which can be scrubbed off. I do agree that it can be scrubbed off and salt is partially to blame, but I disagree that salt reacts with itself to form rust, that metals (typically dissimilar) need to be present. I also disagree that "surface corrosion" should be appearing in less than 3 months. I am somewhat familiar with galvanic reactions between stainless steel and aluminum in the presence of an electrolyte (salt), but would like to know more about this chrome phenomenon. Could it be poor chrome plating causing the salt to initiate the reaction and can I prove it? What other sources of information should I consult? Bottom line, I want a new bumper for my 3 month old $30,000 truck, and to-date the dealership is not cooperating.

Chris Harvey
Engineer/Unhappy Consumer - St. Paul, Minnesota, United States
2004

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2004

Send us a good in-focus close up picture, Chris, and we'll have a better idea of what you are talking about.

Unfortunately some vehicle manufacturers have made it difficult to reach an actual manufacturer's representative and have turned over the decisions on repair/replacement to dealers who probably have absolutely no concept of how chrome plating is done or what is expected of it. I'm curious who in this discussion coined your term "surface corrosion"? Chrome plating is a few millionths of an inch thick, so "surface corrosion" and "catastrophic corrosion failure" are pretty much the same thing :-)

A chrome bumper should not rust or corrode any sooner than the painted body parts. Toyota does very high quality plating; but sometimes something can go wrong, and perhaps this time it has. If it has, I am confident that Toyota wants to know about it and replace the bumper, not have a dealer trying to stiff you.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

Thanks Ted for the information regarding the "surface corrosion" on my Toyota bumper. In following up I am working with my wife to get a good picture, but it's difficult with reflection. The gentleman I worked with at the dealer was the assistant service manager. I met with the actual service manager today and got a similar response, except he used the term "surface discoloration" resulting from chrome and salt reaction. He is going to set me up with the manufacturing rep the next time he comes to town, and I'd like to go in prepared. I've got access to chrome plated steel similar to that used on cars. We test tapes on them for adhesion in the automotive markets. I've also got access to laboratory salt spray chambers in our laboratory. I'd be interested in knowing a good ASTM to follow for my "government work" experimentation. Suggestions for additional responses and rebuttals would be appreciated.

Christopher L harvey
- St. Paul, Minnesota USA
2004

"Surface discoloration", huh? The only surface discoloration I know of is when the chrome was burnt and they didn't color buff the burn out (which sounds extremely unlikely for an OEM part) or when the chrome is missing in a spot and you get the slightly yellowish tone of nickel showing through. But you should see no rust, not the tiniest, tiniest spec, on the outside of the bumper under any conditions.

The way to get a picture is to photograph the reflection of screening, or a very white piece of paper with printing on it.

I don't really know what salt spray testing is going to tell you, and it is of course a destructive test; maybe I'm misunderstanding. I think that your role as the customer only needs to be to note that the plating has failed, not due a failure analysis.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004