open differential

Noun

 * 1)  A type of differential gear used in automobile construction, allowing for output shafts to have different angular velocity, while equalizing torque applied to each output shaft.

Usage notes
Applied torque being output can be modified by appliances external to the differential, such as with a traction control system.

An unlocked differential (unlocked locking differential) functions as an open differential, until locked.

Synonyms

 * abbreviation
 * shortened form