Costco has raised the price of motor oil sold under its exclusive private-label brand, Kirkland, and it's set limits on how much its customers can buy. 

Costco’s Kirkland Signature full-synthetic motor oil 5-quart two pack now costs approximately $58, up from $30 last year, the Associated Press reported. 

The company is also limiting purchases of Mobil 1’s full-synthetic motor oil 1-quart six pack, which sells for about $44, to five per membership. 

Synthetic motor oil is largely dependent on Group III base oils, which are produced by refining crude oil. Approximately 40% of these oils come from the Middle East, where the conflict with Iran is disrupting global supplies.