Ford has shared its concerns with Environmental Protection Agency and California Air Resources Board officials. The investigation does not involve the use of defeat devices in Ford’s products, the company said.

Kim Pittle, Ford’s group vice president for sustainability, environment and safety engineering, described vehicle road load testing in a statement:

Road load is a vehicle-specific resistance level used in vehicle dynamometer testing, including for fuel economy ratings and emissions certifications. Road load is established through engineering models that are validated through vehicle testing, including physical track tests referred to as coastdown testing.

The first vehicle Ford is testing is the 2019 Ranger.

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