WHAT’S INSIDE A DIFFERENTIAL?
THESE days a diff is the term used for the whole drive assembly, including the housing, brakes, axles, etc. But what it actually refers to is the differential gearing assembly inside the heart (carrier) of the diff.
A conventional differential is comprised of four gears. Two are attached directly to the axles, the other two are free to spin on their own axis but are mounted to the carrier, which in turn is rotated by the ring gear.
How do we get the turning power of the driveshaft to the carrier? There are two style of gears normally used: