Federal warranty basics (from the FTC)

Last checked 2026-10-17. Source for this page: FTC Consumer Advice: Auto Warranties and Auto Service Contracts, read 2026-10-17. Not legal advice.

What the FTC page says

A warranty is a promise to fix certain defects or malfunctions during a specific timeframe. A manufacturer's warranty is included in the price of a new vehicle and often covers a certain number of months or miles, whichever comes first.
You do not have to use the dealer for repairs or maintenance to keep your warranty in effect. It is illegal for a dealer to deny warranty coverage because you had routine maintenance or repairs done by someone else.
If the warranty says the work will be done for free, the dealer or manufacturer can make you use repair facilities it chooses; if it says parts are free, they can require parts they choose.
Your warranty stays in effect if you use aftermarket or recycled parts, but the manufacturer or dealer may deny coverage for a part damaged by a defective or incorrectly installed one, and must prove the aftermarket or recycled part caused the damage.
An auto service contract ("extended warranty") is optional, bought separately, and is not a warranty as defined by federal law.
Calls, texts or mail warning that your warranty is about to expire are often attempts to sell a service contract; the FTC says to be cautious.
If you have a problem with a service contract, contact the dealer and the contract company; if that does not work, report to your state attorney general or the FTC at ReportFraud.ftc.gov.

FTC press release on getting the most from your auto warranty (2011): ftc.gov. It says dealers must be able to demonstrate that improper repair caused damage they refuse to cover.
Federal warranty statute text (Magnuson-Moss, 15 U.S.C. 2301 and following), via Cornell Law School: 15 U.S.C. 2310. We link the text but do not summarize it; read it or ask an attorney how it applies.
Find your state's attorney general or consumer office: USAGov directory.

Federal warranty law and state lemon laws are different things. State lemon laws differ widely; start from the state pages.