Tech Tip #114: Available SAE Housing Sizes, Available Clutch Sizes, Torque Capacities & Key Dimensions

Helpful guide for Twin Disc/Rockford PTOs: Available SAE Housing Sizes, Available Clutch Sizes, Torque Capacities & Key Dimensions

Need help sizing a Twin Disc®/Rockford power takeoff? Do you find Twin Disc PTO Model Numbers confusing? The chart below will help you. The first column “PTO Model Number” lists the available Twin Disc power takeoffs by the number of clutch plates and clutch size. In other words, Twin Disc PTO part numbers are based on the physical size of the PTO and its internal components.

The first digit in the alphanumerical Twin Disc model number is the number of clutch plates. The next digit of the Twin Disc model number is the clutch size in inches. Putting this together, a Twin Disc Model C106SP is a single plate, 6″ clutch. The next column lists the available power takeoffs by SAE bell housing sizes. To continue our example, a Twin Disc Model C106HP5 has an SAE #5 housing. If you are rusty on SAE housing dimensions, take a look at our Tech Tip #41, SAE Bell Housings Made Easy!. The next column lists the maximum torque capacity that a particular clutch size will handle. The next two columns refer to SAE duty classifications for PTOs, and the last column gives the weight.

Manufacturers names, symbols and numbers are for reference purposes only and do not imply manufacturing origin.

Written by Dr. Diesel

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