Some 2019-2020 Colorado and Canyon models equipped with the 6L50 automatic transmission (RPO MYB) may have an intermittent slip condition or may not engage when shifted into Reverse.
The intermittent slip condition may be caused by a rough finish on the center support housing damaging the Low-Reverse piston seal. (Fig. 35) If the rough finish is found, replace the Reverse piston seal and the center support.
Fig. 35
During installation of the output carrier assembly, apply automatic transmission fluid to the inside diameter of the output shaft seal before installing the output shaft assembly into the case. The fluid will help prevent the seal from rolling during output shaft installation.
Also, be sure to install the center support retaining ring with the tapered side up and in the 9 o’clock position from the pan side of the case.
Refer to Bulletin #20-NA-062 for additional information and part numbers.
– Thanks to Ron Caponey
