Tensioner - Rattling Noise

[Querys]

Hallo,

Since I have my 2013 Explorer 3.5L TiVCT I have a rattling noise, comming from my V-belt tensioner. It occures during standing/low speed and steering.
The tensioner starts vibrating and this causes the rattling noise.

I replaced the tensioner (quality Motorcraft Part) and put on a new V-belt (Gates).
Furthermore I replaced the AC compressor (Motorcraft Part as well), because the original one was leaking.

Does anyone have a hint, what to do? Because I do not want to replace the alternator just for fun.

 

[Querys]

Anyone any idea?

 

[JAPeterson]

You should be able to pull the belt and check the pulleys and see if there is a problem with one of them.

There could be a alignment issue with the pulleys also.