Noise from front end above 60mph?

[jimp74462000]

My 98 4runner recently developed at noise - more of a humming noise than a vibration - at speeds above about 60mph. It gets worse when freewheeling. Running on cruise above 70mph and I can hardly hear it. Had U joints checked all ok. Had tires rotated and balanced. no good. A friend says it may it the stabilizer bar bushings..?

Any ideas?

Jim