Finding out who makes CT or Walmart's oils seems to be a very hard thing to do up here in Canada. I have a feeling that they might even change their suppliers often on some of the oils too, such as the 0w30 or 5w20.
Thats really wierd. I picked up 8 bottles of the mm 5-20 synthetic in lindsay a couple of months ago and they are all numbered 28-8711 and don't show up on the msds. What is the date printed on the bottle? My bottles say 11/15/06.