Ok i got he whining going on when i give it gas. Replaced the idler pulley and its still there so i am planning on doing the tension pulley. Is it ok just to do the pulley or do i need to do the whole assembly ?

 

Have you pulled the belt yet to determine that it is in fact a driven pulley making the whine? A whine is more likely the alternator or PS pump.

If your battery is on its last legs, a healthy alternator WILL whine trying to keep it charged - have you had it load tested?

 

I have recently been having the same problem within the last month. Now it whines right when I start it up and it seems like it is coming from the drivers side of the hood. Haven't been able to pin it down. I have noticed that when i accelerate it goes away slightly and during decel it comes back on.

 

You too - have you pulled the belt yet?

 

Figured mine out. After replacing the passenger side idler pulley and i still had it. I replaced just the belt tensioner pulley and it was fixed. Each were $20 so i am gonna rlace the drver idler and be done with them .
When doing the belt tensioer pulley just get a long 1/2 breaker bar and loosen from the tensioner and lift the alt belt off. Then install pulley. It does help to have a 2 nd person laying to see that all the belts are lined up

 

Good work.

IT's best to just shotgun it, including the belt - in these cases. It's not expensive ( and even cheaper if you just press in new bearings ), and it' not worth the hassle of R&R'ing the dang belt multiple times as you test each pulley. And if one is going south the rest will likely be along shortly.

Here's John's excellent how-to: https://www.f150online.com/forums/ar...ur-5-4-3v.html

 

Glad you fixed it, but it's not always an idler or tensioner pulley - it can be alternator or PS pump too.

 

Doing the belt system on these trucks is easy. Front wheel drive car are hard. My wifes saturn I've never been able to figure out how to get the belt off the right way. Requires some weird tool that I dont have and I do have the standard belt removal tool. I actually jacked the car up and took the tension off with a block of wood lifting the tensioner up with a floor jack..
I did the whole belt system on the truck when I did the alternator. Its easy.