Mobil Delvac 1 LE 5W-30 full synthetic engine oil:
A fuel economy evaluation was conducted using two Volvo FM440 Euro V trucks, loaded to 75% payload. Testing was conducted on track at the Millbrook Proving Ground, Ltd. in the United Kingdom. Statistically significant fuel economy benefits were observed in the Volvo trucks, when comparing Mobil Delvac 1 LE 5W-30 to a mineral 15W-40 engine oil, with an average fuel economy gain of 1.8% for highway driving conditions. Fuel economy improvements are dependent on vehicle/equipment type, outside temperature, driving conditions and your current fluid viscosities.
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