The PO left a factory transmission filter and gasket in the vehicle. Do you think it wise to do this? I have heard good and bad on this. I will not be using any special thermometer tools or anything like that. If I did it I would drain while warm, replace the filter and gasket and replace the amount I took out. This would be a shade tree mechanic repair. I could flush 3 quarts a couple of times first to save the new filter before replace the filter the last time I guess. What are you guys thoughts and any precautions if I do this? It has 154,000 miles and not sure it has ever been done. Didn't see anything about it on the Lexus web site. Have heard good and bad about doing it with over 100,000.