Is name brand oil sold at walmart the exact same oil as sold in other stores? Specifically I buy pennzoil and valvoline. This may seem like a stupid question but I know walmart beats suppliers down on price. I also know that some products that seem to be the same as in other stores are actually a cheaper version specifically and ONLY for walmart. In my particular case a few years ago I was shopping for a bought a vizio 4K tv. When I narrowed it down to one model and began to look for the best price I found that walmart was $100 cheaper consistently. The series and model number were identical except the walmart version had an extra letter in it. In looking over reviews they always mentioned to be aware that the walmart version was lacking in some features even though it seemed identical to the same model sold everywhere else. Walmart had a special cheaper version made for their stores. The oil they sell is cheaper as well. Is it actually the same liquid that is sold for more everywhere else?