Costco just did something it almost never does with a household staple: it nearly doubled the price of Kirkland motor oil how much any member can buy.**

Costco just did something it almost never does with a household staple: it nearly doubled the price of Kirkland motor oil and capped how much any member can buy.**

The 10-quart case of Kirkland Signature full-synthetic motor oil—the two-pack that millions of DIY mechanics have relied on for years—has jumped from around **$30 to $57.99**. And Costco is now limiting members to **two cases every seven days** .

That's not a minor adjustment. It's a signal that the global supply chain is squeezing one of the most dependable budget products on Costco's shelves.

## Why Motor Oil Is Suddenly Scarce

The culprit is a shortage of **Group III base oil**, the highly refined petroleum product that makes full-synthetic motor oil work . And that shortage traces directly back to the Middle East conflict.

Before the war, roughly **44% of U.S. demand** for Group III base oil came from the Persian Gulf region, primarily Qatar, Bahrain, and the UAE . Then Iranian airstrikes damaged Shell's massive **Pearl gas-to-liquids facility in Qatar**, which had supplied about **30,000 barrels per day**. Repairs are expected to take at least a year .

South Korean refiners, which serve as a backup source, are also struggling to secure crude oil because of their own supply chain disruptions . The result is a cascading shortage that has left blenders and retailers scrambling.

Andrew Lipow, president of Lipow Oil Associates, told the New York Post that the squeeze is concentrated in the premium base stocks used for synthetic lubricants, and that packaging plants are feeling it first, followed by retailers .

## The Refinery Math Nobody's Talking About

There's a deeper economic problem at play. Base oil shares its crude-oil origins with gasoline, diesel, and jet fuel. When refining margins on finished fuels are strong—and right now they're very strong—refiners have a financial incentive to **favor fuel production over lubricant stock** .

The EIA's gasoline crack spread is sitting roughly **$1 per gallon higher** than at the same point in 2025. That gap has squeezed base oil availability and pushed its price upward . Chevron CEO Mike Wirth said last week that the cushions that had softened earlier price increases are now exhausted .

## The Ripple Effects Are Already Here

The motor oil shortage isn't happening in isolation. It's part of a broader energy squeeze that's hitting American drivers from every direction.

**Diesel just crossed $6 a gallon** for the first time in history, sitting at **$6.06** as of Monday . Regular gasoline is at **$4.16 to $4.29** depending on the source .

**Lubricant prices are soaring across the board.** The producer price index for finished lubricants jumped about **15.8% between March and August**. An industry survey of 97 motor oil products found retail prices rose **24.2% from February through August** .

**Valvoline has said** higher lubricant costs are adding roughly **$5 to $7** to the cost of an oil change .

## What This Means for DIY Mechanics

For years, the math was simple: buy Kirkland oil at Costco, do the oil change yourself, and save $30 to $50 compared to taking your car to a shop.

**That math no longer works.** At $57.99 for the case, doing it yourself now pencils out to roughly what a local independent shop would charge . The economic gap that once made the driveway option an obvious choice has closed.

Costco is also limiting Mobil 1 purchases to **five units** per member, with a six-quart case running about **$44** .

## When Will This End?

Don't expect relief anytime soon.

The Independent Lubricant Manufacturers Association has warned that the U.S. base-oil market could remain under pressure **into 2027**, when new domestic Group III capacity is expected to begin coming online .

The shortage has persisted even as shipping conditions have improved because damaged production capacity and depleted inventories cannot be quickly replaced .

Costco hasn't said how long the purchase limits will remain in force. The retailer's terms and conditions note that "quantity limits not applicable where prohibited by law" and that item limits apply "where indicated" . For now, the two-case-per-week cap is the reality.

## The Bottom Line

Costco rationing motor oil is a small story with a big message. It's a reminder that the wars in the Middle East aren't just affecting gas prices at the pump—they're rippling through every product that starts with a barrel of crude oil. And for American drivers who've come to rely on Kirkland oil as an affordable alternative, the squeeze is hitting right where it hurts: the garage.