Hey guys,
I have a really bad whine coming from somewhere, it seems to be at it's worst at 35-45 but only when on the throttle let off the throttle and it goes away. Please help.
thanks

 

Welcome to the club of whiners. Just messing with ya. What type of truck do you have. It seems most trucks that have the 9.75 rear end in them howl at those speeds. Mine does and it is a 2003 5.4L 4X2. It also starts howling around 80mph as well. Some people have been fortunate to get the complete axle housing replaced which seemed to fix it. I guess Ford Engineers found a casting problem with it.

Ford likes to say that it is normal axle whine, but I have had several 9" rear ends (older vehicles) that have never howled like that and were much tougher. Why can't we go back to the good ol' days. So I hope that helps ya, do a search on the topic and you will see lots about it. If it is under warranty try to get them to replace the whole rear axle assembly.

Brian