Costco Begins Rationing Kirkland Signature Motor Oil As Refined Crisis Spreads

Costco’s Kirkland Signature motor oil has doubled in price, and customers now reportedly face a purchase limit as the Gulf energy conflict, combined with the Russia-Ukraine war, has sent the global refining market into a tailspin.

Auto news website The Auto Wire reports that a 10-quart package of Kirkland full-synthetic oil now costs about $58, up from around $30, with a new purchase limit of two packages per week.

Costco’s online sales platform confirms an order limit: when attempting to order three packs, an alert message reads, “Item 997930 has a maximum order quantity of 2.”

Another auto blog, MotorBiscuit, provided more detail on the refining crisis and its impact on the global liquids market:

The ongoing military entanglement with Iran and the blockade of the Strait of Hormuz have effectively choked off these crucial exports. To compound the supply chain disaster, the massive Pearl GTL facility in Qatar sustained heavy damage from Iranian airstrikes in March 2026, instantly crippling a major portion of global production for at least a year.

Refineries Chase 40-Year Profit Highs

Typically, when Middle Eastern supply lines fracture, South Korean refiners step in to pick up the slack. Unfortunately, those refiners are currently struggling to secure raw crude oil themselves.

Furthermore, the petroleum industry is aggressively shifting its manufacturing priorities. Right now, global profit margins for diesel and jet fuel have hit staggering 40-year highs. Motor oil, diesel, and aviation fuel all originate from the same barrels of raw crude. Given the choice between producing essential base oils for passenger cars or cashing in on incredibly lucrative aviation and commercial diesel markets, refiners are overwhelmingly choosing the latter.

This geopolitical squeeze is hitting at the exact worst time for everyday drivers. Today’s highly stressed, turbocharged, small-displacement engines require incredibly sophisticated oil chemistries to prevent catastrophic failure and comply with strict environmental standards.

Because modern engines are so sensitive, automakers demand rigorous chemical testing and licensing. General Motors, for example, requires vendors to pay double licensing fees (both per product and per unit sold) just to print the “Dexos-approved” badge on their packaging. This certification appears directly on Costco’s Kirkland brand.

Combine a fractured Middle Eastern supply chain, international refiners chasing diesel profits, and the expensive licensing fees required for modern engines, and you have the perfect storm for empty shelves.

It’s not just motor oil. Households relying on heating oil face the risk of sharply higher bills as the Northern Hemisphere winter approaches. With the national average retail diesel at a record $6.23 a gallon Monday morning, the squeeze on distillate fuels and other refined fuels is causing a shock. However, electric vehicle owners are just sitting back, watching this all unfold.