ISSAQUAH, WASHINGTON / RankWire.AI / – Costco has increased the online retail price of its Kirkland Signature full synthetic motor oil to $57.99 for a 10-quart case. This package includes two 5-quart bottles and is available in various popular viscosity grades. Additionally, Costco has implemented purchase limits on certain Kirkland motor oil items. Members are restricted to buying a maximum of two units in a single transaction within any seven-day period.
The new price of $57.99 is almost twice the approximate $30 cost reported for the same quantity last year. Costco currently offers 5W-30, 5W-20, and 0W-20 full synthetic oils from Kirkland at this online rate. The retailer emphasizes that prices at individual stores can vary from those listed online. Each case contains 10 quarts, making this price hike particularly relevant for drivers who perform their own routine oil changes.
These purchase restrictions extend beyond Costco’s own brand. Certain Mobil 1 full synthetic motor oils now have a purchase cap of five units per membership. Mobil 1, an ExxonMobil brand, is available in multiple formulations, including standard and high-mileage options. Restrictions also affect six-packs of one-quart bottles across several viscosity grades, broadening the scope of the restrictions to another leading synthetic motor oil brand.
Major synthetic oil brands face new purchase limits at Costco
Synthetic motor oils rely on highly refined base oils combined with additives designed to safeguard engines under demanding conditions. Group III base oils are crucial components in many synthetic lubricants sold in the United States. American consumers depend significantly on imported supplies, including shipments from the Persian Gulf region. Recent disruptions in Middle East energy markets have led to tighter availability of certain petroleum products and lubricant inputs.
In mid-September, crude oil prices remained above $100 per barrel. Brent crude traded around $107.82 on September 16, while West Texas Intermediate hovered near $104.86. Ongoing issues affecting production, exports, and major shipping routes in the Middle East have continued to influence energy markets. Traffic through the Strait of Hormuz remained below usual levels, and disruptions also impacted Saudi Arabia’s Red Sea energy infrastructure.
Rising oil prices coincide with tighter lubricant supply and increased costs
The affected Kirkland products are suitable for many passenger cars, SUVs, and light trucks. Costco states that its synthetic oils help reduce engine wear and prevent thermal breakdown. Selected formulations meet API SP and ILSAC GF-6A performance standards for modern gasoline engines. The American Petroleum Institute manages API motor oil standards, while ILSAC specifications cover areas such as fuel economy, engine cleanliness, and wear protection.
Costco has not provided a detailed public explanation for the increased Kirkland motor oil price or the implementation of new purchase caps. Its online listings currently display the $57.99 price and a restriction of two units per seven-day period on specific products. Meanwhile, separate Mobil 1 listings continue to show a five-unit limit per membership for various formulations. These updates reflect a broader context of elevated crude oil prices and limited lubricant supplies affecting the market.