Where can I get a replacement hollow gasket #521307?

Congratulations! your engine is broken in !!!!!!!
You have nothnig to worry about that is diesel technology. If your truck made it this far you have a lifetime of joyful riding ahead of you.

has different length pushrods.if not in correct locations will damage valves and cause compression issues. a hollow sounding crank?

The magnetic strip (very dark brown) is usually embedded inside a similar square hollow tube all the way around the door gasket. For it to have come out, there has to be a cut, slice or hole in the outer coating of the gasket. Press all the way around the gasket and you should feel the hollow spot where the gasket came out. It will feel solid where the magnetic strip is still in there.

slides out right or left side

Usually the bottom of most framed doors has a chanel which contain door sweep or hollow gasket,all you have to do is pull it and slide the new one in the same place.
Please note that some times the end of the chanel is crimped to prevent the gasket to move in and out of the track.
I hope this will help.

It sounds like you need the sweep or seal that keeps water in the enclosure. You can buy these items, which are inexpensive and usually easy to install yourself at www.technologylk.com Technology LK carries a comprehensive range of shower door gaskets, seals and other hardware. If you have any questions about exactly what you need and how to install it, you can contact the company at www.info@technology.com or call them at 888-663-9830.

Contact KitchenAid directly for information.

sterling is an inexpensive kohler product,....go to a plumbing supply store with your #s and they'll be able to get what you need.

Hollow ice is a sign of not enough water going into tray . Replace the water inlet valve (piece that the wall water line connects to on refrig ) .

Hollow cubes are usually a result of lack of water supply