The stock LS rocker arm from GM is super lightweight and works fine in the stock applications. When subjected to higher lift cams and increased spring rates the stock needle bearing cages have shown their weakness and failed in performance applications. Replace your failure prone and engine damaging stock needle bearings with one of these CHE Trunion upgrade packages. We recommend anyone running stock rocker arms to upgrade them with these. You can even send in your rocker arms for us to Professionally Ultrasonic clean and install. Simply select professional install from the drop down menu above. When sending in your rocker arms for modification please include all of your contact information inside the box. Failure to do so will result in delay of service.