does anyone know if the gmc or chevy 1500s have the 4l80E transmission in them? I know that they do have the 4l60E, but i read that they can also have the 4l80E, but cant find any concrete information on what years they were used. Im looking at 99 and up GMC 1500 trucks with the vortec 5300. The 4l80E is supposed to be much stonger for towing, and has much firmer shifts cause its clutches instead of bands.