Walmart offers a selection of Pennzoil Platinum Full Synthetic Motor Oil, with prices starting from $5. Redeem this mail-in rebate to cut starting prices to $3. (This rebate is for $2 off per quart for a maximum of up to $10 per rebate.) Opt for in-store pickup to dodge the $5.99 shipping fee. Deal ends June 30.
Note: There is a limit of two rebates per person.