Mercedes-Benz has issued an urgent recall for 1 million vehicles including nearly 300,000 in the U.S.
No injuries or deaths have been reported but owners are advised not to drive their vehicles until inspections and repairs have been performed.
The recalled vehicles include ML-class, GL-class, and R-class Mercedes built between 2006 and 2012.
The company said moisture may accumulate and cause corrosion in the brake boosters, which could result in reduced brake performance or brake failure.
The NHTSA said brake failure is rare but it can happen if the corrosion is "very severe” and if there is a “particularly strong or hard brake application.”
The agency said the driver might notice a change in the brake pedal feel and/or hissing/airflow noises before an issue occurs.
Dealers will remove the rubber sleeve, inspect the vehicle and replace the brake booster, if necessary. All repairs will be performed free of charge.