When you buy a vehicle, you can almost set your watch by the time the offers for extended warranties start arriving in the mail.

Most of them convey a sense of urgency, especially if you’ve bought a used car or truck. The “Vehicle Document/Alert Notice” from the “Vehicle Services Department” cautions that an “immediate response” is needed, since “your factory warranty may have expired or will be expiring.”

Could they be a little less specific?

Probably not, because the mouse print notes that you probably got this letter through computer data generated by your purchase.

Is it a scam?

Likely as not, it is. Not all such offers are ripoffs, but the Edmunds website puts it bluntly: “Not every extended auto warranty company is out to rip you off, but over the course of our research, we found that the honest ones are few and far between.”

For an impartial explanation of extended warranties, visit the Edmunds website at edmunds.com/auto-warranty/understanding-extended-warranties.html.

As the Edmunds people explain, companies don’t really offer “extended warranties” in the sense of making a manufacturer’s warranty last longer. Those companies — the legit ones, at least — are offering what are called third-party warranties. Some are good, and some are not. Many are not needed in the first place.

Consumer Reports did a survey a couple of years ago. The average cost of extended coverage was $1,200, and 55 percent of all buyers never used it during the life of the policy. Consumer Reports advised potential buyers to set aside money in a savings account earmarked for car repairs. If needed, it’s there; if not, it’s extra cash.

We’ve written about extended warranties in the past. The subject is worth revisiting simply because of the volume of mail a vehicle purchase generates — our “new-to-us” vehicle this summer prompted 10 solicitations, all of which we declined because the manufacturer’s warranty is in effect for two more years.

The offers don’t always come by mail. Some car dealers will try hard to sell you a service contract as part of the deal.

Do the research and make your own decision; don’t be pressured into an add-on that you feel you don’t need. If you do buy a contract through a dealer, make sure the dealer forwards the payment — to the plan administrator or a third party — and get confirmation in writing.

If the service contract is underwritten by an insurance company, talk with people at the Maine Bureau of Insurance (1-800-300-5000 toll-free in Maine, or 207-624-8475) to see if any complaints are on file against the company.

Since U.S. Fidelis collapsed under the weight of lawsuits from a number of states, solicitors of service contracts seem to have softened their language — there’s less blatant trickery than before.

However, many still use an official-looking American eagle symbol on letterhead and envelopes, even though they have no link to any U.S. government agency. And most will proclaim this mailing is a “final notice.” If only that were true.

You may want to revisit the Edmunds website for a look at third-party warranty scams at edmunds.com/auto-warranty/third-party-extended-warranty-scams.html.

Consumer Forum is a collaboration of the Bangor Daily News and Northeast CONTACT, Maine’s all-volunteer, nonprofit consumer organization. For assistance with consumer-related issues, including consumer fraud and identity theft, or for information, write Consumer Forum, P.O. Box 486, Brewer, ME 04412, visit http://necontact.wordpress.com or email contacexdir@live.com.