Sun gear shaft 4777.307.071 ZF, aftermarket

For the backhoe loaders with ZF axles: sun gear shaft 4777.307.071, an aftermarket part. This part is the splined shaft carrying the sun gear of the planetary hub.

Because the gears in a planetary gearbox work together, wear is usually found on more than one gear, so the sun gear, planets and annulus are inspected together during a repair. A single new gear running with worn ones is noisy and wears quickly itself. The planet gears' needle bearings and pins are checked in the same repair. Tooth pitting is first noticed as bright particles in the oil.

Specifications

Compatibility

According to the product card, ZF 4777.307.071 is a sun gear shaft. Fit is confirmed by the axle type. Other parts are in Carraro.

Fitting

For the change, remove the wheel, drain the planetary oil and take off the hub carrier. Fit the gears with their pins and bearings the right way round, making sure the sun gear circlip seats properly. Renew the gaskets, tighten the bolts to the specified torque and fill the planetary with the specified oil. The gear comes new; before fitting, check the teeth for burrs or impact marks. Hold the planet gear needles in place with grease during assembly.