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Road rash on front bumper

I have a 2 year old pick-up with front chrome bumper. After the first winter, the bumper started to show some sign of pea size rust spots. The dealer polished them off and told me this was caused by sand and stone chips. The second winter, the bumper had 3 times as many pea size rust spots. Again the dealer told me this is caused by sand or stones and called it ROAD RASH. Some of the rust spots were starting to blister.

My question is:-
1)Is chrome plating so soft or brittle that it will allow the sand grains or stones to puncture the layer and expose the steel base?
2)Can anyone tell me where I can obtain information reporting this situation?

Frank Visentin
buyer - Ottawa, On, Can.
April 14, 2008

simultaneous replies

Hi, it is possible that winter weather and stone chips (but not sand particles I would think) will damage the chrome on your bumper - also the salts used to de-ice the roads will corrode your bumpers(via the chip damage) - but your problem could be made worse , if the bumpers were not plated very well in the first place .(due to mass production and rushed plating)

I would have thought that it would have lasted much longer than the first year .

possible cause could be a low deposit of copper and nickel undercoat . the chrome deposit on decorative chrome is very low - we're talking microns . the corrosion resistance would come from the copper / nickel so in my opinion I would say your problem is due to poor plating / or low deposit of plating .
once you have pitting , it will only get worse I'm afraid.

Jay Smith
essex - UK
April 16, 2008

Chrome plating is a decorative effect, not a corrosion protection system. The steel will protect the chrome by rusting preferentially.

Geoff Crowley
Crithwood Ltd.
Westfield, Scotland, UK
crithwood logo
April 16, 2008

Hi, Geoff. It's certainly true that chrome does not protect steel galvanically, only as a barrier layer, but I don't think I'd word it that chrome is not a corrosion protection system. Chrome plated steel bumpers often last decades despite the absolute worst the world can throw at them: sand, salt, heat, cold, sun, frequent cleaning, mechanical bumps, etc.

Frank, the reason that enthusiasts sometimes fit the front of their cars with leather or vinyl "bras" is because the paint will chip because the lower extremities at the front end of a car or truck are exposed to such aggressive road gravel conditions. Keep the bumper clean and waxed or polished. It is possible that the plating is defective, but it is not necessarily so; it's hard to say from this distance.


Ted Mooney,
Ted Mooney, P.E.
Striving to live Aloha - Pine Beach, New Jersey
April 16, 2008

Thank you for your help and information to understand this problem

Frank Visentin
- Ottawa, ON, Canada
April 23, 2008

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