Exclusively for Prime members, Amazon offers Pennzoil Platinum 5W-20 5-Quart Full Synthetic Oil for $11.22 with free shipping via the steps below. That's $2.24/quart, $11 under last week's mention, and the best price we've seen. (It's a current low by $4.) To get this deal:

1. View the Pennzoil Platinum 5W-20 5-Quart Full Synthetic Oil for $24.97
2. order via Subscribe & Save to drop it to $21.22
3. redeem this $10 mail-in rebate to yield a final price of $11.22

Note: Be sure to cancel your subscription once your order arrives to avoid being billed for subsequent shipments. Additionally, this item is temporarily out of stock, but can still be ordered at this price for delivery when available.