Oil pressure gauage reading high

YOur best bet on a truck that old is to install a mechanical oil pressure gauge. They are available at any auto parts store or even Target or Walmart. Just buy the kit and follow the instructions. Mounting and routing the oil line is the hardest part.
It would be very unusual for the oil pressure to be maxed high in a 350 that is over 20 years old so i have to think the issue is the guage.

Very first thing you need to do is install a mechanical pressure gauge on there to verify what you see on your gauge. If the actual pressure is low, then it's time to start looking inside the engine. If not, then you need to trace out the electrical problem but will know the engine is safe.

Oil pressure will increase with PRM's. The hotter the oil the lower the pressure as well.

The higher the oil pressure the better it is, if you had a recent oil change the oil pressure should be high. there is no problem with having high oil pressure.

I think you have a bad ground on your engine gages...but, more importantly, have your oil pressure checked by a mechanic.  If it is indeed only 20 pounds the engine is sadly on it's last legs.
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hi ben
my answer would be yes i would wory about it...
Guages are put on vehicals for a reason not just for looks i would have the car hooked to a diagnostic center and checked even though the guage may be faulty but i wouldnt take a chance

If the weather in your area is colder than normal, your startup oil pressure will reflect this, essentially because it is much thicker when very cold. This high reading should drop to "normal" once it reaches operating temperature. This condition can also be caused by a sticking pressure relief in the oil pump, usually caused by sludge inside the engine. If you regularly maintain your vehicle and use good quality oil, this should not happen. The oil pressure sending unit is also suspect, but in your case, I would not put it at the front of the list. If oil is close to "change time" consider using a good synthetic oil (synthetics flow better at extreme temps) or using a 5W anything oil during winter months. (see manufacturers specs)

Might be that the oil pressure switch is going out. Unless this has been happening for a while now.

if the engine is running normal and there are no odd sounds from engine. probably needs oil pressure switch or bad connection at switch. any ticking noises and i would have pressure checked with guage

I blew a head gasket and the car acted that way. . . sorry