Sonnax Vacuum Testing - 4L60E Pump Cover / Stator Support

Vacuum testing hydraulic circuitry is an integral part of the rebuild process and should be performed on valve bodies and pump stator supports during overhaul to minimize the chances of transmission failure shortly after rebuild. Here, I show how to use the Sonnax vacuum testing machine on a 4L60E stator support aka pump cover. I walk through set up, calibration of the machine along with step by step vacuum testing of the valve trains in the stator support to determine if we need to either install drop‑in 'fix‑it' valves or replace the cover all together with a new and/or good‑used cover.