Walmart offers a selection of Pennzoil Platinum Full Synthetic Motor Oil 5-Quart Jugs, with prices starting from $22.68. Redeem this $10 online rebate to cut the starting price to $12.68. (A $20 maximum rebate applies.) Opt for in-store pickup to dodge the $5.99 shipping fee. Deal ends June 30. Note: There is a limit of one rebate per person.