New supercrew, very satisfied. Passengers often complain about a whistle coming from the floor of the passenger side. I don't notice it unless I'm listening for it, but I'm usually driving. Noise is coming from black plastic AC housing in passenger floor. Only occurs when AC is on. Is this normal? Thanks.

 

I've had 7 F-150's (including a 2007) and never heard a whistle while the A/C was on unless there was a leaf caught in the vents. So, I would say it's not normal.

Hard to diagnose without hearing it in person. Maybe you have a piece of paper, plastic or a leaf in the vent system. Maybe the A/C compressor or clutch. Might be the catalytic converter. Or, it could be they're hearing the faint sound of the engine exhaust. The F-150 cabs are VERY quiet with all that "quiet steel" and my wife gets side tracked when she hears the faint sound of the engine when I step on the gas.

 

Thanks for reply. Actually, the whistle is coming from the black plastic housing around the evaporator. If you press on the black cover, the noise is slighty louder. I can't find any leaks. Sounds like it's coming from the evaporator itself. Problem is completely resolved when AC is switched off, even if fan is still running. AC cools fine. Should I have the R134a levels checked? Thanks.

 

Since you've isolated it down to a particular area, I would definitely take it into the dealer and have them take a look at it.

 

I have an 07 and mine does that as well. Let me know what you find out. Mine has the exct same problem as you. Thanks!

 

Ok...I will keep you posted...I haven't had a chance to check anything yet. Will let you know when I find out.