oil pressure spec. '97 xj 4.0L ?????

checked haynees manual but no luck,
need to know the oil pressre spec. '97 xj 4.0l
gauge is showing low pressure and sometimes shows ok,
an check gauge light comes on
thinking it might be sending unit cause it shows somethimes ok and
other time low
but want to check oil pressure first
so if someone get me spec
it has 250,000 km or around 155,000 miles

thanks

Spec-10-13 psi ,hot,idle(750 rpm) 10w-30 grade oil. Max 75 psi regulated by by-pass in pump.

Wayne

Oil pressure sending units (aka: oil pressure switch in some parts stores) are notorious for failing on the 4.0 Best option is to screw in a mechanical oil pressure gauge where the sending unit is to confirm what your ACTUAL pressure is; a lot of guys just swap out the sending unit and go from there as they are relatively inexpensive.....recommend getting this part from Jeep for best accuracy/mating with your factory gauge.