The shift rod should not be covered with mud and other dirt, so Volkswagen has always protected it with a metal tube.
since this tube is located under the car and little attention was paid to rust prevention, they often get pierced by rust (especially on Volkswagen Buses that were used for professional traffic).
By welding the holes you can get away with it for a while, but it's not a good basis for a restoration, so replacement is the best solution. You are rid of all external influences and also the interior rust, which in many cases is even worse than what you see on the outside.
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