I am very in tune to noises and was the go to guy when I worked at the dealers for rattles squeaks and other unusual sounds to trace out. Our 07 RL has 156,000 on the odo and I have noticed that I think are the front drive axles making some noise in the speed range from 35-50 mph. They don't make thumping noises and the boots are in good shape. I think the grease has worn out and they need to be replaced.

Anyone have any experience on when they should be replaced or when you replaced them?

Acura has good rebuilt axles that are like new but with out the price attached.