A major issue in countries like New Zealand importing cars from Japan is rust under the vehicle.

Snow prone areas like Hokkaido and the Japan Sea coast have world record levels of snow.  To make the roads useable salt is spread on the roads.  This creates a potential rust problem.

Salting the roads in Japan, particularly during winter to prevent ice formation, can contribute to the corrosion and rusting of cars. Here’s how salt can damage vehicles:

1. Salt accelerates corrosion: Salt is highly corrosive and can accelerate the oxidation process, leading to the formation of rust. When salt comes into contact with the metal surfaces of a vehicle, it promotes the breakdown of the protective paint and exposes the metal to moisture and oxygen, creating an environment conducive to corrosion.

2. Salt promotes electrolysis: When salt dissolves in water, it creates an electrolyte solution. This solution enhances the electrical conductivity between different metal components of a vehicle. As a result, it can cause accelerated electrolysis, leading to galvanic corrosion. This type of corrosion occurs when dissimilar metals (such as steel and aluminum) come into contact, leading to the deterioration of the metal surfaces.

3. Salt accumulation in crevices: Salt can accumulate in various crevices, such as wheel wells, undercarriage, and suspension components, where it remains in contact with the metal for extended periods. These areas often have poor drainage and can retain moisture, further exacerbating the corrosive effects of salt.

4. Lack of rinsing or cleaning: If the salt residue is not rinsed or cleaned off regularly, it can continue to corrode the vehicle’s surfaces. Regular washing and cleaning, particularly focusing on the undercarriage, can help remove salt and minimize its long-term effects.

So beware when looking for cars in the Japan car auctions in places like Hokkaido and Niigata, especially when there is the comment on the car auction sheet “rust underneath” or even worse: “### corrosion underneath ###”.