I've got a 240 wagon that is recently new for me. At speeds anywhere from 45 to 65 there is a 'whistle' coming from somewhere outside the car. At first I suspected the factory roof rack was making noise. But as I investigated further I noticed that the noise will come and go depending on if I am on or off the accelerator. Typically makes noise when on the gas, stops or makes less of a noise when off the gas.

I was thinking it may be the drive shaft support bearing, but it doesnt sound like a squealing bearing, not yet at least.

Tonight I was going to squirt a little wd40 on the bearing and see if it temporarily goes away. According the the service records I have it has not been changed in 210,000 miles

Any other thoughts??

-matt

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'93 945 170k, '90 245 210k