Walmart offers the Valvoline SynPower SAE 0W-20 Full Synthetic Motor Oil 5-Quart Bottle, model no. 813460, for $22.97. Choose Site-to-Store pickup to dodge the $4.97 shipping fee. That's tied with last week's mention and the lowest price we could find for this quantity by $13. It purports to offer high temperature, sludge, and varnish protection.