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Auto, oil and lubricant additive industry representatives are continuing their work to draft GF-4, which would be the biggest upgrade of passenger car motor oils since adoption of the Engine Oil Licensing and Certification System in 1993. Automakers have set several goals for the category. One is to lower phosphorus levels to avoid poisoning catalysts in new emissions control devices. OEMs also want oils to provide greater oxidative stability, better fuel economy and better deposit control