By James R. Healey, USA TODAY Honda (HMC) is notifying 6 million owners of Hondas and Acuras that they are entitled to warranty extensions and, in some cases, payments because odometers in their vehicles rolled up miles too fast.

That made warranties expire too soon and hit some lease customers with excess-mileage penalties.

ON DEADLINE: Do you believe your odometer?

A lawyer in the lawsuit that resulted in Honda's moves now is aiming at Nissan, alleging that its Altima sedans back to 2002 roll up miles 2.5% to 3% too fast. Nissan (NSANY) has filed a motion to dismiss the lawsuit but wouldn't say more because it doesn't comment on pending litigation.

The lawyer, James Holmes of Henderson, Texas, says he's tested Toyotas (TM) and, oddly, found them to routinely register slightly fewer miles than actually driven. Detroit brands, he says, "by and large are perfect."

Holmes suspects odometers deliberately are set fast to help automakers trim warranty costs. But the car companies say they're just following an industrywide standard that allows a few percent variation in odometer accuracy.

The Society of Automotive Engineers' voluntary standard is plus or minus 4%, or no more than 4 miles high or low in every 100 miles. The National Highway Traffic Safety Administration says it doesn't regulate odometer accuracy.

Honda says its odometers were accurate to within 3.75% on the high side and 1% on the low side, within the SAE standard. But it says it will extend the warranty mileage 5% and will pay lease-mileage penalties due to fast odometers, at least $6 million just for overcharges on vehicles leased directly from Honda.

Holmes says the fault was noted by Jay Kutchka, a Fort Smith, Ark., lawyer who drove a Honda Odyssey.

Holmes said that once the lawyers investigated, "It was always something like this: 'I used to drive a Mazda, and it was 342 miles to Grandma's. Now I have a Honda, and it's 352 miles.' "

"No odometer is going to be perfect," says Honda spokesman Chris Martin. But prompted by the class-action lawsuit, Honda realized, "The customer expectation is that it would be based on zero. We weren't. So we decided to settle the suit."

Starting with '07 models, Honda tightened its odometer accuracy and centered in on 0%, Martin says.

A U.S. district court in Texas will accept or reject the settlement, probably this summer. Holmes says it's rare for a settlement not to be approved.

Vehicles covered in the deal: 2002 to 2006 Hondas and Acuras bought from April 13, 2002, to Nov. 7, 2006. Some 2007 Honda Fits also are included.