If I put the truck in neutral while traveling, the noise continues as the truck slows down at a lower pitch. My tires do cause some road noise but is different from the sound that I am hearing. The noise you describe may be caused by an axle bearing starting to fail. There is a whining sound coming from the engine when the car is at idle. Also, when I am driving, but the higher the rev the higher the whine.
Several things can be the cause.
First, check the tension on the timing belt to be sure it is properly adjusted. If the car is equipped with an automatic transmission, changing the filter and servicing the transmission may help. This will isolate any of the items like alternator, air-conditioning compressor etc. 60K. Just today, I noticed a howling noise coming from the air intake. The noise does not occur until the engine is in the 3500-4000 RPM range.