1.   American Airlines is offering millions of dollars in mileage credit and fare discounts to settle legal claims filed a decade ago after it altered the terms of its program.

2.   AAdvantage enrollees earn mileage credits when they fly on American.

3.   But the downside to these discounted tickets is that they are usually not refundable, transferrable or good for frequent-flier mileage credit.

4.   Diners Club determines the value of the mileage credit and applies it toward that purchase.

5.   The automakers have used the extra mileage credits to sell more full-sized sport utilities and pickups while meeting the federal standards for average fuel economy.

6.   The Houston-based carrier said it has revamped the way it accounts for the sale of mileage credits in its OnePass frequent-flyer program.