Oil Pressure
Thread Starter
Member
Joined: Oct 2008
Posts: 180
Likes: 0
Year: 1989 2x
Model: Cherokee
Engine: 4.0L Straight 6
How much pressure should the oil gauge read? I recently replaced the sending unit and now my gauge works. I noticed that sometimes at 65 the gauge will read the line passed 40, but sometimes it's at 40. Also if I let off the gas and coast it will drop below 40. So whatcha think?
Junior Member
Joined: Oct 2008
Posts: 38
Likes: 0
From: Boulder, CO
Year: 1988
Model: Cherokee
Engine: 4.0L 258cui I6
Mine is the same way, 218K mi, i've always assumed it was normal, but heard that if it drops much below that its an issue. srry couldn't help more!
CF Veteran
Joined: Oct 2008
Posts: 2,127
Likes: 2
From: Hell, CA
Year: 1989
Model: Cherokee
Engine: 4.0L I6
How much pressure should the oil gauge read? I recently replaced the sending unit and now my gauge works. I noticed that sometimes at 65 the gauge will read the line passed 40, but sometimes it's at 40. Also if I let off the gas and coast it will drop below 40. So whatcha think? 

Trending Topics
::CF Administrator::
Joined: May 2008
Posts: 10,039
Likes: 16
From: Okc area
Year: 1991
Model: Cherokee
Engine: 4.0 I6
Sounds normal to me.. My new motor at idle sits at about 40ish..At driving speeds I sit above the 60 mark. So an older engine will have less oil pressure so sounds good to me. Also if Frankz says it's good I'd trust him he knows engines far better then I..
Thread Starter
Member
Joined: Oct 2008
Posts: 180
Likes: 0
Year: 1989 2x
Model: Cherokee
Engine: 4.0L Straight 6
Ok. I know my rear main needs replacing so I was just making sure that the low pressure wasn't a sign of low oil levels. I check it every few days. Speaking of the rear main. How tough a task am I looking at to replace it?
CF Veteran
Joined: Oct 2008
Posts: 2,543
Likes: 5
From: Stafford,VA
Year: 1998
Model: Cherokee
Engine: 4.0
Transmission has to come out Flexplate/flywheel has to be removed... Its straight forward from there.
You don't what you're talking about. Please don't post unless you do.
Drain and drop the pan.
Remove the rear main bearing cap.
Use a brass punch to push out the upper half of the seal, simply pull the lower half out of the bearing cap
When reassembling use a little bit of light oil to prevent tearing/damaging the seal. I als use a generous amount of Permatex Assembly Lube on the bearing surface and on the lip of the seal (both halves).
CF Veteran
Joined: Oct 2008
Posts: 2,543
Likes: 5
From: Stafford,VA
Year: 1998
Model: Cherokee
Engine: 4.0
ok so your telling me thats the only way to remove the 2-piece seal?? give me a brake
sounds like that is YOUR way of doing it...I however would prefer to pull the tranny. Your method sounds like a half *** way of doing it???
Last edited by 98 JeepJeep; Nov 27, 2008 at 05:56 PM.
CF Veteran
Joined: Apr 2008
Posts: 7,661
Likes: 15
From: Smiths Station, Al
Year: 87
Model: Wagoneer
Engine: 4.0 I6
Frank is right do not post crap on here that you don't know the answer too. I personally have done my Rear main and all you have to do is drop the oil pan it is a easy BUT MESSY task.


