This rear countershaft kit fits Mack and Volvo TRDL/TRDLG-107 and 1070 10-speed transmissions, supporting the countergear cluster that transfers torque between the input and mainshaft. The kit bundles a countershaft, a retaining ring, and installation instructions for a complete replacement. No cross-reference numbers beyond what is already noted are needed to identify fitment.FeaturesRear countershaft kit for Mack/Volvo TRDL/TRDLG-107 and 1070 10-speed transmissionsIncludes GCS-6054 countershaftIncludes GRI-2716 retaining ringIncludes installation instructionsCross-referenced to Mack 25084413, 605KC3105, 605KC3183A, 605KC3183Cross-referenced to Volvo 25084413Tech SpecsFitment: Mack TRDL/TRDLG-107 and 1070 transmissions, 10-speedKit contents: GCS-6054 Countershaft (qty 1), GRI-2716 Retaining Ring (qty 1), Instructions #1267 (qty 1)OEM cross-reference: Mack 25084413, 605KC3105, 605KC3183A, 605KC3183; Volvo 25084413Used in these Mack modelsTRDL / TRDLG 107 / 1070 TransmissionTRTXL-107 / 1070 TransmissionTRXL-107 Transmission