high oil pressure

When I start the blazer everything is fine. After the engine warms up I have problems. When i Accelerate the oil pressure peaks. When i back off the gas the oil pressure drops to less than 40 psi. Sometimes while driving, oil pressure fluctuates from high to less than 40 psi. Blazer is a 1996 4.3 liter v6 170,000 miles. Any suggestions?
Thanks

oil peaks?

You do know the oil pressure will vary with engine rpms.

Oil pressure is going to flutuate with RPM's after warmup. If it is dropping WAY below 40, make sure you have enough oil, and that your oil filter is not dirty before moving on to bigger things.

oil sending units on chevys like to fail, if you clunk, ever, stop, thats when you have an oil issue, but like stated above, oil pressure vaires with rpm's and like i said the sending units like to be faulty on chevys