If the bearings were bad shutting it off and restarting it would not make the pressure return to normal.

 

The oil pressure light will come on at idle if your van needs a tune-up. You will especially notice this if you stop at a stop-light after a really hard run on the highway. I recall seeing this happen on the highway back when I got my van too.
Regards, Steve

 

I have changed the oil pressure sending unit and still have a problem. A manual gauge and the vans gauge both show pressure, but the light comes on. I think the gauge in the dash is bad.

 

Are you certain it isn't the RPM dropping on you from the engine stumbling? The gauges may have dampening on them and not show fast changes.
Steve

 

The light comes on at a steady speed. If I shut it off and restart immediately it goes out.

 

If the mechanical gauge registers about 10 psi per 1000 rpms you are fine the factory gauge light is faulty. Remember there is a reason some call them idiot lights. I just realized you may not have installed a tachometer so just watch the Mech oil gauge your pressure should not drop below 10 psi at idle.

 

never dropped below 15.

 

In my humble opinion you have nothing to be concerned about, maybe remove the bulb.

 

I am going to see if a gauge is available, if not out goes the bulb.

 

FWIW The Magnum engine is known to have oil pump failures...


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