My oil pressure fluctuates high and low. I replaced the sending unit and it didn't change anything. Any ideas?

 

Does it go higher when the engine speed goes up and lower when it goes down?

If so, what's the problem? That's normal.

RwP

 

Sorry, I should have explained it better. When I start the truck it jumps to a spot and doesn't move again until I shut it off. It doesn't move at all after the initial start up.

 

I bet the gauge itself is sticking then.

Good news, you can replace just the gauge (pair, right and left) out of a boneyard cluster.

While the front's off, I'd be relamping that cluster due to age, but that's strictly optional.

(Two or three 8mm or 5/16" head bolts, gauge pair pulls forward, new one plugs in, replace bolts, that part's done.)

RwP