Have a 2002 F250 4x4 with 7.3 diesel with a mystery noise. When I get up to highway speed then lightly let off the gas pedal to just maintain the speed, I hear a faint roaring noise coming from what sounds like the front of the truck. There is a light vibration accompanying the noise. If I accelerate or let off the gas pedal completely, the noise subsides and the truck drives relatively quiet & smooth. If I feather the pedal then lightly touch the brakes, the vibration & noise goes away. It's most noticeable above 65mph. Very audible at 70mph

Both driveshafts feel tight. Just had new tie rod ends and sway bar bushings installed.

There is sometimes a light buckling noise if I turn the truck full tilt like in a parking lot to go in a space. Before replacing the tie rod ends and sway bushings it had a lot of clunking, but most of that is gone now. I still here a light clunk once in a while.

The truck has high mileage so I stopped by a warehouse & picked up two Moog front bearing/hub assemblies. Also have some new rotors coming and reman calipers on the bench. Once the rotors come in I'll work on changing all that out and report back. Figure doing the hubs isn't throwing money away due to the high mileage, and may be a good place to star looking.

Other than front wheel bearings, what else could the roaring noise & vibration be?

 

Updated my question above with a little more detail now that I'm back home from my trip.

 

Bad front u joints.

 

Looks like this would be a good time to replace them regardless. Here's a Youtube showing how its done:

 

Doesn't necessarily have to be front u joints. Could very well be the ones on the driveline. If they are greasable check to see that all are taking grease. I would change the easier ones on the driveline first myself and see if that corrects it.

 

I have Spicer u joints for the main drive shaft and FWD driveshaft, so those will be replaced as well. My rotors & pads need changing, so while I have all that off I thought it prudent to swap the axle u joints while I'm close to them.