Old filling in tooth,dr wants to replace and put crown on.in past diff dr said root wasn't great and glad he didnt put crown.leave this alone?no pain.

Hard to say...: This type of question needs to be evaluated with a radiograph and in person, something that is not possible over the internet. You'll need to have each of your treating dentists explain themselves.

In the middle: You are asking for professional advice without a chance for us to see you, examine you, review your history/medications, and evaluate your x-rays. It's simply not possible. You need to be examined to be advised.