Todd, MB list 13 specific brands of Dextron III fluids you can use. The most common being Quaker State and Penzoil. Contact MB and request a copy of the Approved Service Products List. You will see which fluids/grades them call for.

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1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
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