New Transformer

Sorry but probably not.  As a transformer degrades the insulation breaks down and allows leakage current.  However, by the time the current gets high enough to see on your home feed, it blows.  It doesn't take a very large fault in a transformer to runaway and blow.

  The noise you see at home is more likely the result of unbalanced loads, adding and removing loads, and other system disturbances.  The good news is that often the amount of noise on your system is exaggerated.  

Certainly it can't hurt to have a new transformer. 

Jerry

We had new transformers installed on my rowhome filled street. I can't say for sure if I noticed a difference in the noise floor, there were still ways for other means to contaminate the mains. But we now had rock steady line voltage and no more power outages during storms.

I live in a 60 year old mid century home with the power line running down behind all the houses on the block.  I have always been amazed at how reliable our power has been the 25 years I have lived here.   But over the last 12 months we would hear a loud crack and down we would go but be back up shortly.  Couple weeks ago it happened and we were off for 6 hours and the power company replaced the transformer at 4am in a rain storm. 

You know the power companies, they won’t spend money until they absolutely have to. I would think you should hear an improvement in sound quality.