oil pressure?
#1
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Year: 98
Model: Cherokee
Engine: 4.0
oil pressure?
Hey I was wondering if this is somthing major on my Xj, the oil pressure is between 40-50psi when driving but drops to like 18psi at idle when warm. What could be causing it? I'm running 10w40 right now in it. Thanks in advance
#2
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Year: 1998
Model: Cherokee
Engine: 4.0L
If you are not hearing a ticking noise from the hydralic lifters, your oil pressure is probably fine. In fact if you have over 150k miles on the engine and you have never changed the oil sensor you might want to consider doing that. Especially if you have notice any oil pressure gauge erratic behavior.
I think they are less than $40 and super easy to change.
#3
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Year: 87
Model: Wagoneer
Engine: 4.0 I6
Try changing the oil pressure sender. only a couple of bucks.
If that don't work you could do a major cleaning of your rockers and oil pan. Once you engine warms up it may be loosening up some gunk in there that clogs your oil pump screen.
Just a thought. You can try Seafoaming it... Tranny fluid... Kerosene.... Diesel. But that is a lot of oil changes to get the gunk out. And they don't work well if you have a lot of buildup (Sludge) in there.
If that don't work you could do a major cleaning of your rockers and oil pan. Once you engine warms up it may be loosening up some gunk in there that clogs your oil pump screen.
Just a thought. You can try Seafoaming it... Tranny fluid... Kerosene.... Diesel. But that is a lot of oil changes to get the gunk out. And they don't work well if you have a lot of buildup (Sludge) in there.
#4
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Year: 2004
Model: Grand Cherokee
Engine: 2000 4.0
Sounds normal What is the rpm at 18psi? Mine runs 3-5 psi at idle (confirmed with mechanical gauge) and been that way since I owned it.....no tick or knock,yet.
I plan to pull the oil pan and check/replace bearings, if it comes back to 18 psi I will be ticked pink!
I plan to pull the oil pan and check/replace bearings, if it comes back to 18 psi I will be ticked pink!
#7
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Year: 2004
Model: Grand Cherokee
Engine: 2000 4.0
Factory specs is 13 psi at idle (650). This is used to benchmark clearances in the bearings.....low pressure is not really harmful as long as you have flow...it is the excessive clearances that will cause problems. Some people mistakenly use additivesl to increase pressure but all it does is reduce flow and flow is what you need to get lube to all the bearings. I would not worry about it until I heard some noise. I would use 15-40 wt to compensate for the wear BUT no heavier.
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#8
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Year: 98
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Ok thanks for all the help I guess I'll just run it. I remember it was 40 at idle, about 1100rpm but as long as its normal I'll run it I'm just paranoid LOL
#9
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Year: 1990
Model: Cherokee (XJ)
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What brand of oil filters are you guys with low oil pressure using?
#11
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Year: 1990
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