Oil Pressure Dropping?

Hey all, quick question...lately my oil pressure has been dropping when i'm sittin at a red light or stop sign and even when i'm out wheeling and not moving, when i'm going down the road its alright its about 40 or a tad bit more, i do need an oil change, bout 50 miles over, but its been doing it for a while, it will drop to about 20 and once and while move up and from that and back down to 20 when i'm sitting there, the thing is when it drops i dont hear anything different from the engine like knocking or anything...oh and i theres 120,000 miles on it, anyone know if this is normal or if something is wrong? Thanks everyone!

Dave

Up till the past weekend my 98's would sit around 60-60psi at speed and down to 20 at idle. Changed the oil this last weekend, grabbed what thought was a full case of mobil-1 10W30, got to the shop, put it on the lift, drained, dropped it, changed the filter for another mobil-1 filter and then opened the case. There were 3 bottles of 10W30 and 3 of 5W30, so I used it. Oil pressure at speed and warmed up is just over 40 and at idle just under 20. Will see what happens but as long is it stays around 20 at idle I'm happy. I figure I'm running ~8W30
As for a possible problem, could be your oil filter is plugged dirty and the bypass is kicking in which passes the filter completely.

Factory spec is 13 at idle.

Wondo said:

Hey all, quick question...lately my oil pressure has been dropping when i'm sittin at a red light or stop sign and even when i'm out wheeling and not moving, when i'm going down the road its alright its about 40 or a tad bit more, i do need an oil change, bout 50 miles over, but its been doing it for a while, it will drop to about 20 and once and while move up and from that and back down to 20 when i'm sitting there, the thing is when it drops i dont hear anything different from the engine like knocking or anything...oh and i theres 120,000 miles on it, anyone know if this is normal or if something is wrong? Thanks everyone!

Dave

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Mine started dropping and acting funny. The valvetrain got really loud too. I found that some factory oil pumps are prone to wearing out after 140k or so. I'm at 146k. The HO pumps are aluminum. And i found mine to be self destructing. My pressure got down to 15psi idle and it used to be over 40 always. With the new pump in, it never is under 40 and 75-80 cold! Check with an analog gauge first to verify pressure. If your bottom end is tight, I'll bet it's the pump. Good Luck

FUNKYTEE5

Hey thanks alot everyone for the info!


Dave

Twice now I had low oil pressure problems (180k+ mile 88 4.0L with normally great pressure). The first was when my rear main seal blew and I got down to 2 quarts before I got off the freeway and noticed the 0psi at idle. The second time my oil filter went bad. I didn't know that at the time and put thicker oil in (I was on my way to The Badlands) and got back a little bit of pressure. When I got home someone told me to check the filter so I put another on and, low and behold, the pressure was back.
Jeep on!
--Pete

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