PARKER, Colo (CBS4) When it comes to your large soda order at McDonald’s, you may not be getting what you thought. One customer says their advertised 32-ounce drink is only 30-ounces. Eli Yahalom noticed the difference when he bought a diet coke.

“It felt… like.. smaller than I used to have,” Yahalom told CBS4.

When he got home, he measured it – filling the cup with water then dumping it into a measuring cup. The McDonald’s cup help 30-ounces of water. On the McDonald’s website the large diet coke is listed at 32-ounces.

“It’s false advertising,” Yahalom said.

In a statement, McDonald’s told CBS4, “We are in the process of changing the large cup size for our fountain beverages to 30-ounces, from 32-ounces.”

So in some parts of the country, a large drink is still 32-ounces. McDonald’s said that it will update the website once the system-wide rollout is complete. The fast food chain only charges $1 for any size soft drink, so the price will not be impacted by this change.
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- Written for the Web by CBS4 Special Projects Producer Libby Smith