Jeff,
Does the catridge look like the one above? If so, it can be cleaned and lubricated, or replace it with a new one. I would replace it myself.
Terry

: Please help! My bath faucet is about 15 years old. I have no idea what the make is. It's a single handle with a hollow stem that has a set of o-rings side by side. I have to push REALLY hard and hold it to shut it off. Seems like the water pressure tries to push it back out. Any ideas?

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