Hi guys. I have some problems with my 4l80e. it has to run for a while and I have to go through all the gears before I can drive or it won't shift right. I have to do this after it has only been standing for a few minutes. After I do this, it shifts perfectly. It has new oil and filter.is this normal? Kind of annoying to have to do this every time. Thanks 
Its a 1991 Suburban 6,2D
Its a 1991 Suburban 6,2D