resha

Hello, everyone.

I literally just had a mechanic change out my oil pan gasket, rear main seal, transmission pan gasket and filter, valve cover gasket, thermostat housing, and thermostat housing.

I had all of those changed because my jeep was leaking from various spots. Now that they're all replaced, my oil pressure is low. Does anyone have an idea why? I was hoping maybe an oil change could fix the problem.

RTorrez1

First things first. What kind of Jeep are you talking about? Also engine size.
How low is the pressure? What is the pressure at idle and what is it at operating speed. What kind of oil filter did they put on?That may sound strange but a crappy off brand filter can cause lower pressure on the 4.0.

bigbadon

What kind of oil did your mechanic put in it? What kind were you using before that? How low and at what rpm?

s346k

first rule about oil pressure. check it with a mechanical gauge.

resha

1998 Jeep Cherokee Limited 4.0
Automatic Transmission
Wix 58936 Automatic Transmission Filter Kit
At idle oil pressure is between 0-10
At 2000 rpm's oil pressure is between 20-35
idk the oil filter brand because i had that changed about 4 months ago.
he used cheap oil, which why i was thinking that maybe an oil change with synthetic oil and a new oil filter might help the problem.

RTorrez1

Do like s346k said and verify the pressure with a mechanical pressure gauge. Putting in synthetic oil wont raise the pressure if you have another problem. Unless you put a higher viscosity oil. But that is only a band aid. You need to verify the problem and not mask it.

EZEARL

A lot of work was done around that sensitive sending unit and connector. What pressures were you carrying before the work?

mnewxcv

does it have enough oil? could be low. and if he used 5w20 like a lot of shops are throwing in anything with an engine now, that could cause lower pressure.

s346k

my dash gauge shows the same thing. sometimes it will sit on 0 and make the check gauges light come on. I checked it with my mechanical gauge and determined either the cluster is bad or the sending unit is bad. the jeep actually carries 25-30 psi at HOT idle and 50-55 above 2k rpm. the oil pressure won't be affected +/- 30lbs by "cheap" oil...

resha

I went to another shop and they put in new fully synthetic oil, changed the oil filter, and put on another oil cap (since the first shop that changed my gaskets stripped out the threads on it without telling me). The problem is now fixed. Thanks for the replies.

Gabriel wolf

DOH! Did you check the sending unit at all? Mine reads low but if I jiggle the sending unit a little..presto! It reads just fine...especially after oil changes or any work has been done around that area. You may have just paid for an unneeded oil change...