Tesla Motors said it was reconsidering its use of gag clauses designed to stop owners talking about faults it has fixed in their cars, after a US safety regulator called the practice “troublesome”.

The concession came as the electric carmaker fought to stem concerns about possibly faulty suspensions in its cars, after reports of breakages on several vehicles. The National Highway Transportation Safety Administration said on Thursday that it was examining “the potential suspension issue” and that it was seeking more information from owners and the company.

Requiring customers to sign non-disclosure agreements when the company pays for repairs could prevent them reporting safety problems to regulators and put other customers at risk, said Carl Tobias, a professor at the University of Richmond School of Law. It “is against public policy and might even be illegal,” he said. “They’re saying it wasn’t the intent — but it’s the effect that matters.”