What is this component?

[2KEXP860]

I just bought a used 2004 Expedition (5.4 Eddie B) and I get an intermittent noise from under the hood, passenger side, behind the headlight. It's this aluminum thing and when it turns on it shakes violently and makes quite a racket. Only does it when the car is cold, after it heats up it doesn't do it. Sometimes it will do it once other times it may turn on/off 4-5 times or so.

 

[1997SCEBFEX]

air compressor for your air suspension.
it has two components, the 12v side which makes the air, and the dryer on top to keep condensation from getting into your air lines.

 

[2KEXP860]

Great thanks for the quick reply! I'm guessing it shouldn't be this noisy or is it ok?

 

[1997SCEBFEX]

True statement.

As they age, they will [eventually] deteoriate and get noisier. The rubber bushing mounts also wear out too, the replacement bushing mounts are much better

My original unit had a catastrophic failure in the Spring of 2011, thus lasted 14 years, when the crankshaft inside busted in two. They're [pretty] easy to replace, but the tear-down removal of the battery, battery box, washer reservoir etc. takes a little time and marking what came from where before reassembly is the key.

 

[2KEXP860]

Awesome. Thanks for your help!