2000 Expedition 5.4L suspension/drivetrain issue.

[$100T2]

2000 Expedition Eddie Bauer 5.4L 4x4.

I'll do the best I can to describe this:

Driving down the road, there is a whirring sound. It increases or decreases with the speed of the truck. Veering left makes it go away. Veering right results in no change.

I described the problem to a mechanic. He told me it was most likely a hub. I ordered a hub and replaced the driver's side. The sound is still there, but now will go away if I go over bumps/hills/anything that unloads the suspension.

I assumed it was the driver's side because by veering left, load is taken off the driver's side suspension.

The only other things I can think of are:
1) Bad alignment
2) Tire out of balance
3) Bad ball joints

Those are just guesses. The out of balance tire should be an easy enough test by just cross rotating the tires. If the symptoms change, that would show something is up with the tires.

Any other ideas?

[99Expy]

Have you serviced the rear differential? I have seen several post on this forum where noise came up from the rear end. Just a thought.

[TBIRD430]

Power steering fluid flush??

[$100T2]

Originally Posted by 99Expy

Have you serviced the rear differential? I have seen several post on this forum where noise came up from the rear end. Just a thought.

It definitely sounds like it's coming from up front, but I'll check that.

Originally Posted by TBIRD430

Power steering fluid flush??

I don't think that would do anything. Like I said, the noise is directly related to wheel speed. It's not a power steering issue, it's a rotating drivetrain issue.