2005 Mercedes Benz CLK 320 Technical Service Bulletin # S-40_10-18A Date: 080201

Wheels - Recommendation Against Chroming Alloy Wheels
Date: February 2008
Order No.: S-B-40.10/18a
Supersedes: MBNA 40/18 dated April, 1991
Group: 40
Revision History
Revision Date Purpose
a 02/2008 Updated to include current models
- 04/1991 Initial issue
SUBJECT:
All Models
Chrome Plating of Mercedes-Benz Light Alloy Wheels
Warning!
Chrome plating of Mercedes-Benz light alloy wheels is not recommended.
The reason that we do not recommend chrome plating is as follows:
When chrome plating an Mercedes-Benz light alloy wheel, the wheel must first be anodized (copper plated).
The difference in EMF (Electro-Motive Force) values between copper and aluminum results in electrolytic corrosion with aluminum being the
sacrificial metal. This will result in weakening of the base metal as well as poor adhesion of the subsequent plating, and thereby premature flaking of
the chrome finish.
Wheels of cast light alloy, with their porous surface, are even more susceptible to this condition than those of forged light alloys.