Consumer Reports, which many consumers use when studying what vehicles to buy, said the Japanese automaker's decision to call for a service campaign or a warranty extension on two different problems covering cars from model years 2007 to 2011 does not go far enough. Under a service campaign, an automaker repairs cars as they are brought back to dealers by consumers.

"Consumer Reports believes that Toyota should recall these cars," the magazine said. "What’s at issue here is a series of acknowledged defects in a crucial safety system.

"A recall is more comprehensive and widely published than a mere service campaign, and owners don’t have to wait for a problem to happen before qualifying for the repair," Consumer Reports added. "Besides that, unlike extended warranties, recalls don’t expire and are performed proactively."

Toyota officials did not have an immediate comment.

Consumer reports said Toyota's decisions were prompted partly by consumer complaints filed with U.S. safety regulators at the National Highway Traffic Safety Administration. The complaints over the last several years have covered loss of braking performance, increased effort to press the brake pedal and other difficulties, the magazine said.

NHTSA opened a "preliminary evaluation" probe into an estimated 30,000 Camry hybrid sedans from model years 2007 and 2008 after receiving 59 complaints of intermittent loss of assisted braking, resulting in increased stopping distances.

A preliminary evaluation is the first step in a process that can lead to a recall if regulators determine that a manufacturer needs to address a safety problem.

Consumer Reports, which pointed out that Toyota's service campaign and extended warranty both broadened the scope of the potentially affected vehicles, said its review for the two model years NHTSA cited found power-brake complaints had risen to 269, with 14 crashes and five injuries.

In the service campaign, a problem is potentially caused by a clogged brake-fluid reservoir filter and "front-brake assist could be temporarily lost," according to a Toyota notice to its dealers. Instead of a recall, Toyota will alert owners to the campaign to install a new brake reservoir tank at no cost between now and June 30, 2017.

In the other case, Toyota is extending warranty coverage of the anti-lock brake system's brake actuator from the standard three years or 36,000 miles, to 10 years or 150,000 miles, according to a separate company notice to dealers. Remedies could include a new actuator or the reprogramming of the skid control electronic control unit.

(Reporting by Ben Klayman in Detroit. Editing by Andre Grenon)