[dclonch1]

DO NOT - i repeat - DO NOT let a shop "flush" your transmission fluid. My family owns at least 3 silverados/sierras and I can tell you from experience that this is a bad move. What it does is jars every little bit of crud loose from your tranny and lets it recirculate into the system. My dad said that a tranny shop told him that they see a lot of these transmissions coming in for rebuilds because the owner had the tranny flushed and it jarred buildup loose and glogged channels in the tranny. Just service your tranny like you should and don't worry about the flushing service. It can do more harm than good.