How to Convert a GM 4L60E Transmission to a 4L65E - Car Craft Magazine
There're better options for the 3-4 clutch pack than the Z-pack in Article above, depending on how much HP/TQ you're gonna throw at it. Best = Raybestos Blue Plate Specials, Better = Ray. Stage 1's or Alto Red Eagles, next High Energy's .
More >> GM's Stronger 4L65-E Transmission-Super Chevy Magazine
65E's Output Shaft is also an upgrade.