(MONEY Magazine) – When Sears Automotive Centers were accused in early June by California and New Jersey regulators of overcharging their states' car repair customers, drivers everywhere got a reminder: Choose your mechanic as carefully as you would a physician, or risk your car's health and your own wealth. California officials allege that drivers were charged up to $585 for unnecessary brake work. (Sears has since stopped paying mechanics on commission.) Three tips for choosing an auto shop: -- Once your car's warranty has lapsed, seek referrals from friends and associates. Then telephone your local consumer-protection office to avoid shops with troubling complaint records.

-- Don't assume that dealer service is always best. In his 1991 surveys of 52,000 repair shop customers in San Francisco and Washington, D.C., Robert Krughof of the nonprofit Center for the Study of Services found that consumers were satisfied with dealerships only 74% of the time, vs. 92% for independent garages. ''The independents live by their service. They want people to come back,'' says Krughof. ''Dealerships rely much more on sales of cars and parts for their profits.'' -- Favor shops approved by the American Automobile Association. Each year the AAA inspects repair shops nationwide that ask for certification and surveys 75 customers at each to gauge their level of satisfaction. Today, only one out of 100 shops, or 4,000 nationwide, have the AAA's approval. All AAA shops offer free 90-day/4,000-mile warranties and guarantee that the cost of work won't exceed their initial estimate by more than 10%, unless you are consulted. ''AAA approval is far from a guarantee,'' says Krughof, ''but 79% of customers at AAA-approved car dealers, for instance, report being satisfied, vs. 72% at non-AAA locations.''