Recent updates from DGI’s global procurement and supply network.

Component Guide: Upgrading Caterpillar 777B Transmissions and Differentials


DGI Australia’s ongoing component guide series outlines how to quickly and accurately identify or upgrade major OEM components.

This month, we’re highlighting how to easily and effectively modify a Caterpillar 777B transmission to suit a later-model 777C or 777D model truck. We’ll also shine a light on the similarities and differences between the differential and bevel gear, which are able to spec up to an E series truck with further modification.


A testament to the sound design and engineering implemented across Caterpillar’s range of trucks, the modification involved in this upgrade is relatively simple.

A 777B contains transmission 9W-9303, while and 777C and 777D run the 8E-9035 transmission. To update the 9W-9303 to the 8E-9305, simply install the updated hydraulic control valve.


A Caterpillar 9D-2315 777B differential and bevel gear contains the diff centre 6G-7506. Similarly, 777C, D and E model trucks contain the same 6G-7506 diff centre within their differential and bevel gear assembly, with the part number 104-9410.

The major point of difference here, among smaller necessary modifications required to upgrade, is the main housing.

DGI specialises in sourcing and distributing Caterpillar off-highway truck components, internationally. We are consistently identifying ways to minimise operating costs and maximise the output of our clients’ mining and construction machinery fleets.

Our dedicated on-site facilities and OEM-trained specialist team give us a competitive advantage, allowing us to bypass rigorous identification and administrative processes, solving your problems faster and more economically.

View our live component inventory or contact our friendly sales team today to discuss a wide range of available products and solutions to suit your operations.

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