Will using a JuiceBox with a higher electrical output than my vehicle's on-board charger cause damage?
No, using a higher amperage charging station will not harm your vehicle. The vehicle's on-board charger limits the charging current the vehicle can accept.
For example, if the vehicle has a 32A on-board charger and you plug in a JuiceBox 40, the vehicle will charge at a maximum rate of 32A.