Walmart offers a selection of Mobil 1 and Mobil Super Motor Oil 5-Quart Bottles in a variety of grades, with prices starting at $14.28. This mail-in rebate drops the starting price to $7.28. (The rebate amount varies based on the type of oil you buy.) Opt for in-store pickup to avoid the $5.99 shipping fee. Check here for eligible products. Deal ends October 31.

Note: Although Walmart is not specified on the rebate, customer service states that this list is not all-inclusive, as it reads "some participating retailers".