Oil pressure has been dropping over the past week, engine has roughly 170,000 on it, at idle or a stop light, im sitting at about maybe 10-15 psi, while driving, 13-1500 rpm im not even hitting 40 psi, ironically, i have subsequently started to develop a slight knock. Other than that, it runs good, temp wise like 200 ish, this is my daily driver, was thinking if i put a new oil pump in it, i could buy some time, yey or ney?????

 

What brand of oil filter is currently on the Jeep?

 

Oil pump won't help you if your bearings are the root cause.

First thing I always do with low oil pressure readings is "verify". Get a mechanical gauge on there and then you'll know for sure. Good data = good decisions. Many parts stores will rent you this gauge inexpensively.

Oil pressure spec for the 4.0 is as follows:

*Not less than 13 psi at HOT idle

*Between 37-75 psi OVER 1600 rpms

 

my oil pressure dropped low- it was my oil sending unit...

 

Yup Lisa, that possibility is why he should "verify" it. You cannot trust only one source for oil pressure data; it is not uncommon that there can be inaccuracy between the oil pressure sending unit and the dash gauge. Slapping a mechanical gauge on for a reading is the first thing a shop tech. would do.

 

I had my oil changed a couple of weeks before my sending unit went out--I found out that they put cheap oil and filter in it and put a quart and 1/2 to much oil in it(that is messed up)-GRrrrrrr- it was the same place i have been going to for years for a oil change- but they sold the company and I didnt know that it had new owners--SO I had to change my oil and filter again-- That might be the reason why my sending unit messed up in the first place??Dunno? Its hard to trust anybody to do work on your jeep-even when you are there watching-dont turn your back!!..

 

Bringing this up again:

There is a thread on Jeepforum about the oil passage to the sending unit being clogged with crud. Removal of the sender and using a zip-tie to wiggle around in the passage seems to have solved a few low oil pressure problems for people.

I will be trying this SOON on my 92.. I replace the pump last winter.. Helped a little. Mechanical guage says 2 PSI hot.. No knocking or ticking.

 

This one?

http://www.jeepforum.com/forum/f19/4...fixed-1304679/