front end noise

[sparky3241]

I have recently purchased a 2008 expy ironman edition. Recently I have been hearing a humming noise coming from where I believe to be is the front end. Naturaly I changed the front drivers side bearing. This was not the issue.
It seems to be the loudest around 70mph, increases with speed, not with the rpm's. If I put it in nuetral and rev the engine nothing changes. As I said, I have changed the front bearing and nothing. Anyone have any ideas ? I could use some imput.

 

[scubastevesx]

hello i had a humming coming from my front tires when i bought my
06 explorer had the dealer check the wheel bearings they said they
where fine. i was going to change the tires anyways. i don't trust the
les swab brand tires. so long story short put some yoks on the truck
fround that the wheel tpms sensors had broken bands that solved
some of the problem with just a tires. but the noise was still
slightly there came down to rear wheel bearings all noise is
gone now. i would rotate your tires have them checkeded
and have the rear wheel bearings looked at. big o did mine for
277 a side have them put your truck on a rack and have it scoped