To avoid contact corrosion, use only genuine Audi parts (bolts and attachments). Damage caused by contact corrosion is not covered by the warranty. Box gears with magnesium housing can be recognized by the inscription "Mg Al 9 Zn 1", which is located on the left side of the box.
The gearbox with a magnesium crankcase is designated by the inscription "Mg Al 9 Zn 1", the arrows show the locations of this inscription
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