95 Blazer Oil Pressure problem.

Hello everyone, I have a problem similar to the one Mcar posted. 95 Blazer with a rebuilt 4.3 recently installed. Seems to run fine, a little rough and takes longer than I would expect to start but otherwise ok. During city driving the oil pressure remains near or above the midpoint on the gague but after an hour or so of driving or a highway trip of 20 miles or so when I have to come to a stop the oil pressure gague will drop to near the red zone. The engine sounds normal and doesn't stall but the needle is right on top of the red and then goes back up to near middle when I accelerate again. This morning it was different though. A short trip to get coffee and at every stop the needle would bury itself in the red and the check gauge light comes on. Accelerate and the needle jumps back to near normal and the light goes off but it happened again at every stop. If anyone has suggestions I will be glad to hear them. I'm 45 miles away from my mechanic and do not want to destroy the beast driving back to the city. Feel free to respond by email if you like. enomai@gmail.com. Thanks,
Matthew

My oil pressure does the same thing but it doesn't go near the red zone.I have a crate engine and have about 5000 mile on it.I did notice that when I ran 10-30 oil, the pressure went lower when the oil was hot.What weight are you running?

its Chevy there oil pressure indicators have always gone crazy. Im not sure about how 2 fix it but i see it a lot. as long as you are getting oil pressure i wouldnt worry about it.

Try replacing the oil sending unit, it's a common problem for these to go bad...