Diesel fuel starts to weaken as quickly as it is produced. Within 30 days of refining, all diesel fuel regardless of brand, goes through a natural procedure called re-polymerization and oxidation. These components now drop to the bottom of the fuel tank and kind asphaltene also known as diesel sludge. It is approximated that eight out of every 10 diesel engine failures have actually been directly associated with poor quality and contaminated fuel.

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