Review security and quality certifications, such as ISO procedures or equivalent shop standards

https://wiki-net.win/index.php/Durable_Driveline_Rebuilds_and_Balancing:_A_Buyer%27s_Guide_to_Custom_Fabrication_and_Truck_Parts_Quality

Review safety and quality certifications, such as ISO procedures or comparable shop standards, calibrated equipment schedules, and technician training qualifications.