ISSAQUAH, WASHINGTON / RankWire.AI / – Costco has raised the online price of its Kirkland Signature full synthetic motor oil to $57.99 per 10-quart case. The package includes two 5-quart bottles and is offered in various common viscosity grades. The retailer has also imposed purchase restrictions on certain Kirkland motor oil products. Members are limited to buying no more than two units per transaction within any seven-day span.
The current price of $57.99 is nearly twice the approximate $30 reported for the same quantity last year. Costco lists 5W-30, 5W-20, and 0W-20 Kirkland full synthetic oils at this online rate. The company notes that prices can vary between different warehouses and what is listed on its website. Each case holds 10 quarts, making the price increase significant for drivers who perform their own routine oil changes.
The purchase restrictions extend beyond Costco’s private-label products. Certain Mobil 1 full synthetic motor oils now have a purchase cap of five units per membership. Mobil 1 is an ExxonMobil brand available in multiple formulations, including standard and high-mileage options. Restrictions are also applied to six-packs of one-quart bottles of various viscosity grades, broadening the limits to another major line of synthetic motor oils.
Restrictions on major synthetic oil brands expand
Synthetic motor oil relies on highly refined base oils blended with additives designed to protect engines under demanding conditions. Group III base oils are key components in many synthetic lubricants sold in the United States. U.S. consumers depend heavily on imported supplies, including shipments produced in the Persian Gulf region. Recent disruptions in Middle East energy markets have limited the availability of certain petroleum products and lubricant inputs.
In mid-September, crude oil prices remained above $100 a barrel. Brent crude traded near $107.82 on September 16, while West Texas Intermediate was close to $104.86. Energy markets continue to reflect disruptions affecting production, exports, and major shipping routes in the Middle East. Traffic through the Strait of Hormuz remains below normal, with additional disruptions impacting Saudi Arabia’s Red Sea energy infrastructure.
Rising oil prices coincide with tighter lubricant availability
Many passenger cars, sport utility vehicles, and light trucks use the affected Kirkland products. Costco states that its synthetic oils help safeguard engines against wear and thermal breakdown. Some formulations meet API SP and ILSAC GF-6A performance standards, which are designed for modern gasoline engines. The API oversees motor oil standards in the U.S., and ILSAC specifications cover areas like fuel efficiency, engine cleanliness, and wear protection.
Costco has not provided a detailed public explanation for the increased Kirkland motor oil price or the new purchase caps. Its online listings currently display the $57.99 price alongside the two-unit seven-day purchase limit on selected products. Meanwhile, separate Mobil 1 listings continue to restrict sales to five units per membership across various formulations. These adjustments situate Costco’s motor oil pricing and buying regulations within a broader context of elevated crude oil costs and constrained lubricant supplies.