Was there ever a verdict in the issue of the loud grinding noise at the startup of the air conditioning on the 3d gens? I have heard mine twice, and today was really loud, it actually made the same sound as when the T case gets shifted from N to 2H, and vice versa. Thanks for any input

 

I'm not sure of any grinding noise, but I know there was a topic of the A/C having a clunking sound upon turning the compressor on. Is that what you were talking about, as far as it goes for the clunking sound, everyone says its normal. But to me it just doesn't sound right...

 

Ditto on the clunking sound when the compressor first starts up on my '06. Haven't asked my dealer yet, but it sure doesn't sound right when it kicks in.

 

Agreed. The thing sounds like it's gonna come right apart. Nasty.

 

Mine sounds more like something is gettin shredded under the hood, thats the only way I know how to describe it. If anybody has any insight on this I too have been curious as to if it was a problem.

 

Could be the compressor clutch. Do you see any metal shavings around the clutch? Also check the idler pulley.

MikeyB

 

Exactly. Like a spoon in the garbage disposal

 

The sound you are hearing is because the liquid r134 is collecting in the compressor after the vehicle is turned off. Same problem Ford is having in there new Expeditions. Ford also says that will not hurt anything. I have changed the compressor on the Expeditions and has fixed the problem. I would talk to the local Service Manager about getting it fixed.