I stopped in WM at Georgetown, Texas today to grab some oil filters for one of my diesel tractors, and checked the ST bottles a little closer than last week. QS High Mileage v. ST High Mileage, ST Full Syn, v. QS Q Syn, ST Dexron III v. Penzoil Dexron III, and the production codes all show the same respective plants of mfg. with the most of the production dates being in late 2006/early 2007. SOPUS may be cheaping down the ST products to meet WM's price points but the products are coming from SOPUS.
"I was in a Walmart in Austin looking at all of the ST Bottles, 5qt, 1qt, High Mileage, Synthetic, regular and not only are the bottles the same shape as Penzoil and QS, but the production codes are in the same format and and location as the Penzoil and QS. Having checked my PP stash for production date, I recognized some of the ST oils even had the same HLPA prefix as my PP. I compared a few of the comparable oils like ST High Mileage and QS High Mileage and several had the same plant prefixes. Anectdotal observations but I would wager that lots of ST products on Texas shelves are coming from SOPUS."