I just completed a auto to NV4500 conversion about 2-3 weeks ago. I had an NV4500 rebuilt by a reputable transmission shop here in Pittsburgh Pa that has worked on them before. I used mostly new parts, new master/slave, new clutch, pressure plate, throwout bearing etc... . I am having trouble shifting into 1st and 3rd. I rarely ever use 1st. For 3rd gear it seems like it doesn't shift smoothly from 2nd to 3rd. Sometimes I hear a slight grind. I used fluid straight from the Dodge dealer with the correct part number. Could it be just fluid, should I try Amsoil or is it something else. Thanks Pete