Whining noise

[Mikegraves777]

Ok so I have looked at numerous threads and cannot pin point anything. I have a whining noise that I hear more under truck than near engine bay. If u take screwdriver like a stethoscope and put it to muffler u can hear noise loud if u put it to transmission u hear nothing. The noise is not heard when truck is cold only makes Noise after truck is completely warmed up. The noise
Is still there if u remove belt also. It's been at the dealership for a week now and they cannot figure it out. The truck is a 2008 with 26000 miles I bought from a ford dealership and the warrenty is through them, they may be sending it to a dodge dealership tomorrow. Jus curious if anyone can pin point this. I seen a video on YouTube of truck making exact same noise and someone commented that it was pulley bearing but dealership is saying it's not. Any help would be appreciated. Jus is odd to me that it only does it when truck gets warm. Also it does not get louder as I accelerate and u cannot hear the noise inside the cab jus when ur stop or idling.

 

[Mikegraves777]

Truck has been to three dealerships one couldn't figure anything out one said it is normal and the last one said he thinks it's a dry seal. I don't know what to do its so damn annoying. The noise is not there until warmed up and the noise is still there if you take belt off. Any suggestions? Would a dry seal really make a whining noise and will it go away if it is a dry seal?

 

[Redtruck-VA]

Sometimes an exhaust manifold will leak when cold and stop leaking as the engine/manifold warms up.

 

[Mikegraves777]

The noise is only there when truck is warm

 

[Redtruck-VA]

Ok, misread. I'll take it since you are under the truck that this is happening when sitting still and has nothing to do with the truck moving. Does the whining increase with engine rpm?

 

[Mikegraves777]

No it doesn't increase

 

[Chris Walker]

Did you ever figure out this issue? Sounds like the exact same problem that I am dealing with mine at 30,000.