Many an engine has been destroyed as a result of oil pump driveshaft failure. To cure this all-too-common problem, ARP has designed an extra heavy-duty shaft that will provide you with the necessary reliability. The shaft is made from premium grade 8740 chrome moly steel and heat-treated to 190,000 psi. The shaft diameter is a larger diameter than the OEM unit, and ARP uses a unique manufacturing process where the alignment sleeve is roll formed onto the shaft (not welded or pinned), enabling the sleeve to float and allowing for slight misalignment. These features combine to enable ARP shafts to handle the added torque requirements of increased capacity oil pumps or heavy viscosity lubricants.