Among the problems discovered by inspectors were "four undercarriage frame cracks including at the drive axle, at the cross member for the motor mounts, and at the differential and over the right front steering axle, " according to a letter sent by Berwick to Federal Motor Carrier Safety Administration Administrator Anne Ferro.

WSJ: Mass. official: Buses pulled from road for safety

Each of the four wheels contains an electric motor, drive train, suspension and steering and braking mechanisms.

FORBES: Magazine Article

Drivers with arthritic hands, painful or stiff fingers or diminished fine motor skills should look for cars having a thick steering wheel (even better for those living in northern climates, a heated steering wheel) and easy to operate gearshifts.

FORBES: Best New-Cars (And Features) For Senior Drivers