General information about the front differential (Discovery 3)

Contents: Operating principle of differential ⇩ Service ⇩

Item name	Spare part catalog number	Description
1	-	Right front axle shaft
2	-	Front differential assembly
3	-	Front drive shaft
4	-	Left front axle shaft

The front differential changes the torque transfer angle by 90° and distributes the torque between the front wheels via the axle shafts.

The front differentials for models with V6 and V8 petrol engines have the same gear ratios. The gear ratios in models with the TdV6 engine differ depending on whether the transmission is installed: automatic or manual.

The front differential is mounted on the left side of the chassis.

Operating principle of differential

The front and rear differentials operate in the same way. The rotational motion of the cardan shaft is transmitted through the primary flange to the pinion shaft and the drive pinion. The angular position of the drive pinion relative to the driven pinion ensures that the rotational motion is transmitted at an angle of 90°.

The rotational motion is then transmitted to the driven gear, which in turn sets the cup in motion. The shaft, which is attached to the cup, rotates at the same speed as the cup. The planetary gears mounted on the shaft also rotate with the cup. The planetary gears, in turn, transmit the rotational motion to the right and left sun gears, which rotate the drive shafts.

When the car is moving in a straight line, the torques transmitted by the differential to each sun gear are equal. In this condition, both drive shafts rotate at the same speed. The planetary gears do not rotate and securely fix the sun gears to the cup.

When a car turns, the outer wheel rotates faster and travels a longer distance than the inner wheel. The differential determines the difference in torque between the sun gears. The planet gears begin to rotate on their axes, allowing the outer wheel to turn faster than the inner wheel.

Service

The differential uses Castrol SAF-XO oil. This oil contains unique additives that improve the operation of the differential. It is prohibited to use any other oil in the front differential.

The article was copied from a resource (lrman.ru)