I sent a sample of Amsoil ACD which was in my car for about 5k, and sat through the winter. I think it went out on either the 31st or 1st and have not received an email yet. I can drive to Ft Wayne in a few hours, so I would think that the good old postal service would have had my sample there by now. I also had a TBN done this time which I haven't done before, which may add to the time needed? I don't know, I just don't remember my previous samples taking this long for results.