Ok heres the problem. I have a 2005 f150 with the 5.4. only problem I have had is a slight exhaust manifold leak but nothing major. Here is the issue, it started about two months ago. I had a squealing noise which only occurred under acceleration which was believed to be an idler pulley. Well a month of replacing pretty much the whole front of the motor (all pulleys and belt, even harmonic balancer), still no luck. This squeal even occurs with the belt off the truck. This is what happpens, I start the truck is squeals real quick and goes away. Then only occurs if I'm driving and accelerate moderately to hard. I can not get the truck to squeal while in neutral or park, only drive. What makes no sense to me is it makes that quick squeal right when i start up the truck. But the whole problem needs to be resolved, all I can hear is that it is coming from the passenger side of the motor. I am lost. Help ME!!!!

 

Hi - I deleted the other thread you started on this problem. Please don't start multiple threads on the same subject. It leads to confusing responses that waste everyone's time, including yours.

I was going to guess a loose serpentine belt, but then I reread your post. Since it occurs with the belt off the truck, it would have to be something that is moving that is not belt driven like an engine or wheel bearing. Or, could it be something in your suspension? You don't say how long the squealing lasts.

I had a squealing noise from the driveshaft due to a worn universal joint one time way back in the 70s. But, it was obviously coming from the rear center of the vehicle, and, once it started, it was constant.

- Jack

 

My wild guess is torque convertor.

Is your trans fluid full and how dirty is it?