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, which includes two 5-quart bottles, available in multiple common viscosity grades. The retailer has also implemented a purchase limit for certain Kirkland motor oil products, allowing members to buy no more than two units in a single transaction within any seven-day period.
This new price represents nearly double the approximate $30 level recorded for the same quantity last year. Costco currently offers 5W-30, 5W-20 and 0W-20 Kirkland full synthetic oils at that online rate. The company notes that prices can vary across individual warehouses compared to what is listed on its website. Since each case contains 10 quarts, this significant increase impacts drivers who perform their own routine oil changes.
The purchase restrictions extend beyond Costco’s private-label offerings. Certain Mobil 1 full synthetic motor oils now have a limit of five units per membership. Mobil 1, an ExxonMobil brand, is available in various formulations, including standard and high-mileage options. The restrictions also cover six-packs of one-quart bottles in several viscosity grades, broadening the scope to another leading synthetic motor oil line.
Restrictions on major synthetic oil brands are now in place at Costco
Synthetic motor oil relies on highly refined base oils combined with additives designed to safeguard engines under tough conditions. Group III base oils are crucial in many synthetic lubricant formulas sold in the United States. American consumers depend heavily on imported supplies, including shipments originating from the Persian Gulf region. Recent disruptions in Middle East energy markets have reduced availability for certain petroleum products and lubricant components.
Crude oil prices remained above $100 a barrel into mid-September. On September 16, Brent crude traded near $107.82, while West Texas Intermediate was around $104.86. The energy markets continue to reflect interruptions affecting production, exports, and key shipping routes in the Middle East. Traffic through the Strait of Hormuz stayed below typical levels, and disruptions also impacted Saudi Arabia’s Red Sea energy infrastructure.
Rising oil prices coincide with tighter lubricant supplies
The Kirkland products affected are suitable for many passenger cars, SUVs, and light trucks. Costco states its synthetic oils help prevent engine wear and thermal breakdown. Some formulations meet API SP and ILSAC GF-6A performance standards for contemporary gasoline engines. The American Petroleum Institute administers API motor oil standards, while ILSAC specifications cover fuel efficiency, engine cleanliness, and wear protection.
Costco has not provided a detailed public explanation for the increased Kirkland motor oil prices or the new purchase caps. Its online listings currently show the $57.99 price and a two-unit limit per week for certain products. Meanwhile, separate Mobil 1 listings still show a five-unit limit per membership on various formulations. These changes reflect a broader trend of elevated crude oil prices and constrained lubricant supplies affecting Costco’s pricing and purchasing policies.