Chris
Active Member
EPA doesn’t rate them; RAM submits the data to the EPA, which is then either approved or not (which leads to other things, such as requesting further data).The problem with TFL running a 98 mile loop at 70 mph to see what highway mpg is, it is not how the EPA rates the highway mileage. This is ok for real world testing, but won't match EPA numbers.
You are correct in that it isn’t the way the EPA data is generated; but, as appears to be the case with Ford, that submitted data can still be manipulated to get EPA approval when it may not meet the intent of the EPA rating.
As you are likely aware, the federally regulated EPA ratings came about to combat the deceptive advertised mileage claimed by manufacturers. Since then, it is also used to determine if the manufacturers are meeting federally mandated minimum mileage requirements to avoid fees and other additional activities. If it turns out the manufacturers found a loophole to manipulate those ratings, or worse, outright lie about them (like diesel emissions defeating software), the EPA is not going to be happy.