It was the proposal that brought every automaker selling in the North America market out in a cold sweat.

Now, Reuters brings news that the NHTSA and the Environmental Protection Agency (EPA) are delaying the 54.5 MPG, 2025 average fleet fuel economy figure proposal until November.

The reason given for the delay is the complexity of the 2,000-page proposal, which needs a little more time to complete. The plan is being drawn up by the NHTSA, EPA and California Air Resources Board and equates to an average 5-percent per year increase in fuel efficiency from now until 2025 - though lower for larger vehicles.

It's also expected the proposal is taking time to appear to give the car industry, consumers and environmental parties time to raise any issues that might be encountered.

The plan, agreed to earlier this year by the Obama administration, has come under strong opposition from auto dealers who describe the rule as "too much, too fast". This is despite the manufacturers themselves agreeing to the standards, and the 2025 date giving them enough time to implement changes.

The challenge isn't as tough for some makers as it sounds. Some cars already get very close to the average 54.5 MPG corporate standards and some manufacturers such as Hyundai are expected to meet the target several years early. Trucks will also be allowed some leniency to meet targets more gradually. The Detroit News reports that trucks are expected to achieve around 44 MPG by 2025, with regular cars around 62 MPG - a proportionally greater fuel saving than cars will manage.


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