Although not limited to@ these flywheels are normally used on trucks considered as Medium-Duty (Class 6 and 7)@ as well as Heavy-Duty (Class 8) trucks. Purpose??This SAE Recommended Practice defines flywheel configurations to promote standardization of clutch installation and mounting dimensions for flywheels used with pull type single- and twin-plate truck clutches
SAE J1857-2017 history
2017SAE J1857-2017 Flywheel Dimensions for Truck and Bus Applications
2003SAE J1857-2003 Flywheel Dimensions for Truck and Bus Applications
1997SAE J1857-1997 Flywheel Dimensions for Truck and Bus Applications
1987SAE J1857-1987 Flywheel Dimensions for Truck and Bus Applications@ Recommended Practice