CAT TH55 7-Speed to 9-Speed Conversion Parts

Innovative Solutions to Challenging Problems

When Supply chain shortages left rebuilders without the necessary parts to build TH55 9-speed transmissions, Trans Machine created a solution for the market. In collaboration with several customers, we designed and tested modifications to 4 key components and also manufactured one new component. This allowed rebuilders to use parts from a 7-speed unit in a 9-speed unit. Not only did this solve a supply chain problem, but it also provides the ongoing benefit of substantially reducing the cost of parts needed to convert a 7-speed unit to a 9-speed unit, or to rebuild a 9-speed unit containing damaged components.

Not just a solution, but a solution true to our quality standards.

As with all our restoration and remanufacturing processes, our goal is to match OEM durability, performance, technical specifications, and appearance. All these elements must come together to satisfy our quality standards. Even our modification designs and processes have these standards in mind, ensuring that you can install these components with pride and confidence.

TH55 Components Converted for 9-Speed Functionality

Rear Cover Modification

  • 7-speed part number 269-8202 Modified to function as part number 370-2791

Housing Assembly Modification

  • 7-speed part number 297-8406 modified to function as part number 373-2984

Carrier Housing

  • 7-Speed part number 292-0078 modified to function as part number 362-7865

Hub Assembly

  • 7-Speed part number 273-1734 modified to function as part number 382-6062

TH55 New Parts

  • Plate Assembly – Part Number 354-6865

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