ISSAQUAH, WASHINGTON / RankWire.AI / – Costco has increased the online retail cost of its Kirkland Signature full synthetic motor oil to $57.99 for a 10-quart pack. This bundle includes two 5-quart bottles and spans several commonly used viscosity grades. Additionally, Costco has enforced a purchase cap on this item, allowing members to buy no more than two units per transaction within a seven-day window. This restriction appears on select Kirkland Signature motor oil listings on the company’s website.
This elevated price represents a significant jump from figures reported about a year ago, when the same quantity was approximately $30. Presently, Costco offers various Kirkland full synthetic formulations online at $57.99, including 5W-30, 5W-20, and 0W-20. It’s worth noting that in-store prices may differ from those online and can vary depending on the location. Each package contains 10 quarts, making this price increase particularly noticeable for customers purchasing oil for regular vehicle upkeep.
The purchase limitations also extend to several Mobil 1 products available at Costco. Mobil 1, an ExxonMobil brand, is among the most recognizable synthetic motor oil brands in the United States. Now, six-packs of one-quart bottles have a limit of five units per membership. The affected listings include both standard and high-mileage formulations across different viscosity grades. Consequently, these restrictions go beyond Costco’s private-label motor oil and encompass a major national lubricant brand.
Restrictions Apply to More Than Just Kirkland Oil
The production of synthetic motor oils relies on refined base oils and additives that meet current engine protection standards. Group III base oils are a key component in many synthetic formulations. The United States depends heavily on foreign suppliers for these materials. A significant share of the global Group III output comes from producers in the Persian Gulf. Recent disturbances in Middle Eastern energy markets have restricted supplies of various petroleum products and refining inputs used by the lubricant industry.
Meanwhile, 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 near $104.86. Energy markets continued to reflect disruptions affecting key Middle East production and shipping routes, with traffic through the Strait of Hormuz remaining significantly below normal levels. Additionally, Saudi export infrastructure on the Red Sea experienced interruptions, further stressing regional petroleum supply chains.
Broader Supply Challenges Impact Synthetic Oil Availability
Costco’s affected Kirkland offerings include grades suitable for many passenger cars, SUVs, and light trucks. The retailer states that these oils offer wear protection and help prevent thermal breakdown. Selected formulations meet API SP and ILSAC GF-6A standards, which cover engine cleanliness, fuel economy, and resistance to specific types of wear. The Mobil 1 products listed at Costco also include various standard, fuel-economy, and high-mileage options.
Costco has yet to provide a detailed public explanation for the increased prices of Kirkland motor oils or the introduction of purchase limits. Its online listings currently display both the $57.99 price and the two-unit purchase restriction on certain items. Meanwhile, separate Mobil 1 pages continue to show a five-unit limit per membership for several formulations. These changes come amid rising crude oil prices and tighter lubricant supplies, with Costco’s posted restrictions offering members clear guidance on current availability and purchasing procedures.