The NHTSA is looking into Ram pickups (2013-16) and Dodge Durangos (2014-16) with transmissions controlled by “the knob,” a dial shifter whose design was inspired by commercial trucks.

There have been 43 complaints out of around a million sales (0.0043% of sales), with 25 reported crashes. The Rams and Dodges are alleged to have rolled after the driver moved the gear selector to Park and left; most complaints say that the engine was running at the time.  None of the owners appear to have been using their parking brakes.

Ram’s knob has a clear, mechanical-feeling tactile response, with wide gaps between gears to help in gear selection, which is not universal practice for dial shifters.

The NHTSA is conducting a preliminary evaluation, not a full investigation, at this time, and may find that user error is to blame for the complaints.

FCA’s Eric Mayne wrote: “FCA US is cooperating fully with NHTSA's investigation, the scope of which is limited. Other vehicles equipped with rotary shifters are not included. In accordance with prudent practice, the Company joins NHTSA in urging all drivers to use their vehicles' parking brakes.”