OK guys, '87 Dodge D-150 318-2v. I finally got it unstuck from the snowbank on Saturday only to discover that when its warm it has ZERO oil pressure at idle. Hit the gas and at about 2k RPM its somewhere between 20 and 25 on the mechanical gauge. And when its cold its about 25 at idle but as it warms up the pressure drops off. You can even see the clear line to the gauge is empty.

You can hear also the lifters clattering faintly but no bottom end noise.

So, what did I do to it? 187k miles BTW. Spun bearing, worn cam bearing? I havent driven it at all since I discovered this just ran it in the drive checking things.

And yes its full of oil BTW.