Actually Mobil has seven, that's right, seven different 0w-20 offerings. Marketing must come into play. Can't imagine the formulations being that much different. I'd pick the ESP version, but that one does not have a Dexos1 approval for use in GM vehicles.
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Mobil 1™ Extended Performance 0W-20
Up to 20,000 miles of outstanding wear protection – guaranteed.
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Mobil 1™ ESP X2 0W-20
Helps prolong the life and maintain the efficiency of emission systems in new, emerging diesel and gasoline powered European vehicles. An advanced full synthetic motor oil.
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Mobil 1™ Truck & SUV 0W-20
Extra protection for hardworking truck and SUV gasoline engines.
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Mobil 1™ 0W-20 Advanced Fuel Economy
Outstanding engine protection and potential fuel economy benefits.
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Mobil 1™ Extended Performance High Mileage 0W-20
Up to 20,000 miles of outstanding wear protection for high mileage vehicles – guaranteed.
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Mobil 1™ High Mileage 0W-20
Vehicles with more than 75,000 miles need extra care. Keep them on the road with Mobil 1™ High Mileage 0W-20 synthetic motor oil.
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Mobil Super™ Synthetic 0W-20
Provides long engine life and outstanding protection in vehicles of all ages. A full synthetic motor oil.