ISSAQUAH, WASHINGTON / RankWire.AI / – Costco has raised the online price of its Kirkland Signature full synthetic motor oil to $57.99 for a 10-quart case. The package includes two 5-quart bottles and comes in various common viscosity grades. The retailer also implemented a purchase limit for certain Kirkland motor oil items, allowing members to buy no more than two units in one transaction within any seven-day window.
This $57.99 price represents nearly a doubling from the approximate $30 cost for the same quantity reported last year. Costco lists 5W-30, 5W-20, and 0W-20 Kirkland full synthetic oils at that online rate. The company notes that prices may vary across individual warehouses compared to its website listings. Each case provides 10 quarts, making this price hike particularly relevant for those who perform their own oil changes regularly.
The purchase restrictions extend beyond Costco’s private-label offerings. Certain Mobil 1 full synthetic motor oils are now limited to five units per membership. Mobil 1, a brand owned by ExxonMobil, offers various formulations including standard and high-mileage types. Listings affected by these restrictions include six-packs of one-quart bottles across multiple viscosity grades, broadening the scope of restrictions to another significant synthetic motor oil brand.
Restrictions on major synthetic oils include Costco’s private-label options
Synthetic motor oils are formulated using highly refined base oils combined with additives designed to safeguard engines in tough conditions. Group III base oils are integral to many synthetic lubricants sold in the United States. Consumers in America rely significantly on imports, including shipments originating from the Persian Gulf. Recent disruptions in Middle Eastern energy markets have restricted the availability of certain petroleum products and lubricant inputs.
Crude oil prices stayed above $100 per barrel in mid-September. On September 16, Brent crude traded close to $107.82, while West Texas Intermediate was around $104.86. The energy sector continues to reflect interruptions affecting production, exports, and key shipping routes in the Middle East. Shipping through the Strait of Hormuz remained below normal levels, and disruptions also impacted Saudi Arabia’s Red Sea energy infrastructure.
Rising oil prices coincide with limited lubricant supplies
The affected Kirkland products are suitable for many passenger cars, SUVs, and light trucks. Costco claims its synthetic oils help prevent engine wear and thermal breakdown. Several formulations meet API SP and ILSAC GF-6A standards, which cater to modern gasoline engines. The American Petroleum Institute supervises API motor oil standards, while ILSAC specifications address aspects such as fuel economy, engine cleanliness, and wear resistance.
Costco has yet to provide an in-depth public explanation for the increased Kirkland motor oil prices and the new purchase limits. Its online listings currently show the $57.99 price and the two-unit weekly restriction on specific items. Meanwhile, separate Mobil 1 listings continue to display a five-unit membership limit across multiple formulations. These changes reflect a broader context of elevated crude oil prices and tighter lubricant supplies, influencing Costco’s pricing and purchasing policies for motor oils.