OIL PRESSURE READS WAY PAST MAX

Oil pressure on MAX when the truck off off,when I
start my truck,the oil pressure shoots way past
MAX, my engone is running great..no noises,lots
of power&all my other gauges are working
perfect,Please help...I own a 2005 Chevy Silverado
4×4 half ton truck 4.3 litre v6;I dont want to wreck
my engine that only has "124,000"kilometers(just
over 65,000 actual miles),Im fairly handy around
automobiles&I have my own tools,any ideas on
trouble shooting?I need the truck for work..but im
scared to move it because I dont want to wreck my
engine,my engine is not making any noises,and
has lots of power&the other gauges appear to be
normal and in normal operation mode...except for
the oil pressure,this just started acting up
yesterday...I was driving it for 10-minutes all
gauges were normal,then all of a sudden the oil
pressure gauge started climbing,I drove it like that
for 2-minutes ay very low speed,when I stopped
tbe truck &turned it off in my yard,the oil pressure
gauge read way past MAX,after the truck sat for 3-
hrs,I opened the truck&without turning the engine
on...the oil pressure gauge still read MAX...&when I
started the teuck...the oil pressure gauge
immediately shot up to way past MAX,again;no
engine noises,no loss of power,just that oil
pressure gauge shooting way past max...and its
freaking me out....please help