Well, after trying to research the topic of M1 in my tranny I decieded to try it my self and see how it would run.
2005 Chevy Silverado, 5.3 Vortec, 4L60E tranny with external tranny cooler and motorguard byass filter.
This is what I did,
-I unhooked the cooler lines, put out line in a bucket...