Hi. I would have searched for an answer but apparently either I am an idiot or I would need to upgrade my account.
At any rate, my neighbor has a Grand Cherokee with a 4.0. Not sure on the year but I am guessing around a 2000ish. At idle the oil pressure shows zero and the check guages light comes on. At cruising speed it will come up to about 40 PSI. I installed a new oil pressure switch and it is still doing the same thing. The Jeep has had this problem for about 2 months now so I am guessing it doesn't have low oil pressure although I haven't confirmed this with a mechanical gauge. I did read through the forums a bit and saw a few posts relating and most replaced the sending unit and all was better. My neighbor had gotten a new sending unit from Carquest or Napa, can't remember, but is this an item that should be an OEM piece only or will an aftermarket work fine? If it is a problem with the gauge, can I replace just the gauge or do I need top get them a new cluster?
Sorry for all the questions. I'm a tech for Audi, so not totally car stupid but it's been a long time since my independant shop days and dealings with anything domoestic. Any help would be great.