I just changed the two faucet stems and there still a drip.
Does your tub have a third handle to switch from tub to shower? If so, check the bibb washer on the center diverter handle.
If you have a small pull up handle on the tub spout in most cases the problem is because some of the metal around the spout diverter seat has corroded away. Simple solution is to change the spout.
Found the problem. First it is a delta faucet. After I changed the O ring for the spout and that didn't work. I did the next best thing I called Delta. They told me there was a spring and a rubber cup at the base of the stem and that was the only thing left to change. They were correct. Problem solved. Thanks for you reply.
In the future, change the spring and rubber seats first. Usually that takes care of the drip.