I know this is a question that when I hear the answer I'll kick myself for not knowing it sooner, but can someone tell me what this gizmo is? It's from the top of the air cleaner on my W-150, I don't know what part to be looking for in my catalog.

 

It is part of the HIA, Heated Inlet Air System. Called a Vacum Diaphram that actuates the Air Control Valve which blocks cold air from entering the snorkel and allows hot air to enter from the exhaust manifold oven.
Maybe called a Air Control Valve Diapram. I'm just guessing at that description.

 

It's not needed. It does supposedly help on engine warm up. If you have emission testing you will need it..

 

Here's where it goes:

 

Thanks for the info guys, this will be a Northern truck so I will probably keep this part to help the warm-up. Skwerly, excellent reply just the same!

 

Haha, I couldn't resist.

 

Chances are that the old heat-riser from the exhaust manifold, rusted off a decade ago anyway!

 

A functioning choke should really be all you need.