Check out Consumer Guide's chart of model-year 2010 new-car warranties. Click here for the full list.

A new-car factory warranty is the auto manufacturer's pledge to absorb certain repair and replacement costs until a specified period of time elapses or the car has accumulated a stated number of miles--whichever comes first. The limitation is expressed as number of years/number of miles. Here's an overview of how manufacturers' new-car warranties work and what they generally cover.

Bumper-to-Bumper Warranty

The basic warranty is "bumper-to-bumper" coverage for the entire car. It generally excludes tires and the battery, which are covered by their own manufacturers.

Warranties are generally described as "limited," which affirms that they don't cover everything that might go wrong with the vehicle. Most basic warranties exclude:

• Normal wear and maintenance items (oil, filters, brake linings).
• Damage from the environment (hail, floods, "acts of God").
• Damage from improper maintenance.
• Damage caused by the owner or vehicle occupants.
  

Several manufacturers include free scheduled maintenance that covers routine work such as oil changes and wiper-blade replacement. Some maintenance coverage lasts for the duration of the basic warranty; some maintenance coverage lasts for a shorter period.

Extended Powertrain Warranty

A separate extended powertrain warranty that extends beyond the basic warranty is often offered. This applies to major components such as the engine, transmission, and driveshafts.

Corrosion Warranty and Roadside Assistance

The corrosion warranty covers "perforation" rust and extends beyond the basic warranty. Free roadside assistance that offers on-the-road help is often included with most new vehicles for a specified time period. Sometimes, corrosion coverage and roadside assistance coverage is offered for a stated number of years, but with no limit on mileage.

Government-Mandated Warranties

The federal government requires three other warranties. Two federal emission-control warranties exist. Both cover emissions-related parts for 2 years/24,000 miles, plus 8 years/80,000 miles on the catalytic converter and any on-board diagnostic device. These warranties cover emissions performance (whether or not the car is able to pass an emissions test) as well as design and defect issues. The Passenger Restraint Warranty covers seat belts and airbags for 5 years/50,000 miles.

If the original factory warranty has not expired when the vehicle is sold, often the warranty may be transferred to the new owner, either at no charge or for a fee. Specific second-owner exclusions may apply to leased and fleet vehicles. The details vary by automaker.

03.12.2010