High Pitch Jet Turbine-Like Whine
Hello all. I just bought a 2007 es350 yesterday with 67k miles. When I test drove the car, the highway was too congested to get the car above 50 mph. So, the car sounded fine to me and I purchased it with a free 90 day, 3k mile powertrain/engine/transmission warranty. The car should still be under its standard 7 year 70k mile warranty as well, right?
Fast forward to today. The highway was less congested and I was able to get the car up to 80 mph. However, I noticed a constant hum start at 60 mph, which became louder and more high pitch at 75 mph. Im taking this back to the Lexus dealership from where I purchased it to get the sound diagnosed and repaired, but thought I'd see if anyone here has had a similar issue or know what the problem could be? I'm hoping it's a problem still covered by the warranty, like the differential (does the ES350 have a differential since it's fwd) or pinion bearings. Could it be something simple, like a bad tire?