It is common for one of the three plastic retention tabs to break on the wiring harness case pass-through connector in GM 4L80-E and 4L85-E units. This allows the connector to be pushed into the case when connecting the external harness. Not only does this require extra labor to fix, it also requires a new wiring harness. Sonnax wiring harness connector bracket 34998-01K retains the internal harness connector even though the retention tabs may be broken.
4L80-E and 4L85-E units use two different wiring harness connector styles. The early style has exposed terminals and a red rubber gasket. The late style has a gray plastic enclosure surrounding the terminals. The Sonnax bracket 34998-01K works only with the late style connector.