Mechanical Components and Functions: Differential

2007 Ford Fusion SEL, 2.3 Z, StandardSECTION Differential
WARNING: This page is about a different car, the 2010 Mercury Milan and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

The differential allows the halfshafts and wheels to rotate at different speeds during cornering and transfers power to the Power Transfer Unit (PTU) for All-Wheel Drive (AWD) vehicles.

The differential assembly consists of the following components:

  • Differential case (part of the final drive carrier)
  • Two pinion gears supported by a pinion shaft
  • Two side gears supported by the differential case and halfshafts

When driving in a straight line, both front wheels rotate at relatively the same speed. This means both side gears are rotating at the same speed, as well, while both pinion gears revolve (but do not rotate) with the side gears. During cornering, the wheel on the outside of the turn is forced to rotate faster than the wheel on the inside of the turn. Since the side gears must now rotate at different speeds, the pinion gears rotate on the pinion shaft allowing the drive axles to rotate at different speeds while still transferring output torque.

Fig 1: Cutaway View Of Differential
G06278141Courtesy of FORD MOTOR CO.

Differential Exploded ViewΒ 

Fig 2: Exploded View Of Differential
G06278142Courtesy of FORD MOTOR CO.
ITEM DESCRIPTION

Item Part Number Description
1 7F465 Differential housing
2 - Pinion shaft
3 - Pinion gears
4 - Side gears
RENDER: 1.0x

NO RELATED

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