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 and comes in various common viscosity grades. The retailer has also implemented purchase limits on certain Kirkland motor oil items, restricting members to buying no more than two units in any seven-day period during a single transaction.
This $57.99 price is almost twice the approximate $30 cost reported for the same quantity last year. Costco lists 5W-30, 5W-20, and 0W-20 Kirkland full synthetic oils at that online price. The company notes that prices at individual warehouses can vary from those posted on its website. Since each case contains 10 quarts, this price hike is particularly relevant to drivers who perform routine oil changes themselves.
The purchase restrictions also extend beyond Costco’s private-label oils. Certain Mobil 1 full synthetic motor oils now have a limit of five units per membership. Mobil 1, an ExxonMobil brand, offers multiple formulations, including standard and high-mileage options. The affected Costco listings include six-packs of one-quart bottles across various viscosity grades, broadening the restrictions to another major synthetic motor oil line.
Restrictions cover key synthetic oil products
Synthetic motor oils rely on highly refined base oils combined with additives that safeguard engines under demanding conditions. Group III base oils play a significant role in many synthetic lubricants sold in the United States. American consumers depend heavily on imports, including shipments produced in the Persian Gulf region. Recent disruptions in Middle East energy markets have reduced availability for some petroleum products and lubricant components.
Crude oil prices remained above $100 a barrel in mid-September, with Brent crude trading near $107.82 on September 16 and West Texas Intermediate at around $104.86. Energy markets continue to show effects from disruptions impacting production, exports, and key shipping routes in the Middle East. Shipping traffic through the Strait of Hormuz stayed below normal levels, and Saudi Arabia’s Red Sea energy infrastructure also faced disturbances.
Rising oil prices tighten lubricant supplies
The affected Kirkland oils are suitable for many passenger cars, SUVs, and light trucks. Costco states that its synthetic formulations help prevent engine wear and thermal breakdown. Some of these meet API SP and ILSAC GF-6A standards, which are designed for modern gasoline engines. The API standards are overseen by the American Petroleum Institute, while ILSAC specifications cover aspects such as fuel economy, engine cleanliness, and wear protection.
Costco has not provided a detailed public explanation for the increased price of Kirkland motor oil or the new purchase restrictions. Its online listings currently show the $57.99 price along with a limit of two units per week on certain products. Meanwhile, separate Mobil 1 listings still display a five-unit limit per membership for several formulations. These changes place Costco’s motor oil pricing and buying rules within a broader context of elevated crude oil costs and limited lubricant supplies.