1998 Cherokee Oil Pressure issues... I know common question

I am having what I can see is a common issue among many cherokees.

I have 98 cherokee, 133k. semi-Low oil pressure while driving (30-35), and sensor trips at warm/hot idle when stopping (drops below 13?), Pressure is 50 at start up.

Changed sensor to OEM, changed the oil pump today to a new OEM mopar (ya lots of work...).

Still same issues, motor seems to run ok, plenty of power. Have noticed it runs at about 215F-220F, a little past the center in town driving and right on the half mark on the freeway.

Old oil pump looked well used, maybe the oil had not been changed as regular as it should have been.

What else can I do?? I do not want to get into the bearings and such in the motor as I dont have the garage time to do that, I basically rent my brothers garage to do all the work.

I am concerned about it, I dont know if I should continue driving it, it runs fine, doesnt overheat and doesnt have any hard work its doing, no towing right now or naythign like that. motor doesnt seem noisy, not for a 4.0.

I am running SAE 30, I put in a Wix filter for that model motor, etc.

Any tips, tricks to get the pressure up, I was thinking 20-50?

What filter DO increase pressure from your firsthand knowledge?

Is thier maybe a problem with the cluster? Id start off by putting a gauge on the oil pressure system, and see where it goes from there. I would stick with a Wix, Napa Gold, K&N, or ACdelco oil filter. Run what stock calls as far as oil goes.

The Wix oil filter is reputedly one of the best brands so stick with it.
You've changed the oil pump & oil pressure gauge sending unit, and you're still getting low oil pressure readings so that rules out the oil pump, sending unit, or the oil pressure relief valve as possible reasons.
That leaves either worn bearings or a faulty gauge. Check the oil pressure with a mechanical gauge and if it matches the reading from the dash gauge, you're left with worn bearings as the only remaining cause of low oil pressure.
If that's the case, you could raise the oil pressure by using a thicker oil e.g. 20W-50. The engine could run quite happily like that for several thousand miles before you'll need to rebuild it.

Sound like time for Slick 50. The teflon clogs up the major oil bleeds enough to raise pressure 20-30 pounds. I'm still using 10-30 and haven't had to retreat in three years.

I've run it dry - no oil on the stick - and frequently on two quarts often enough before I got a pan leak under control. It won't cure blowby, tho.

YMMV!

I will try the 20w-50 and the slick 50, I will get back to you all and let you know

The Teflon from Slick 50 can block small oil passages inside the engine so I wouldn't use it. Just use a good quality 20W-50 dino oil without putting any additives in it.

Bought the 20w 50, ill try that solo, and I heard soeone mention something about sea foam? what are some great Oil additives out there for tired motors?

Never had anything but good things happen using Slick 50. I've used Slick 50 High Mileage treatment in every engine I've had in the last 15 years. While only one of these vehicles is a Jeep, in all cases, I didn't start using it until engines were almost at 100k - after they are nice and broke in

Since the engines had high miles, I used Rislone to flush them first. Flush regimen is add Rislone when oil was low, run engine 5 minutes, drain, add new cheap oil filter, cheap oil (30 weight) and more Rislone, run for 5 minutes, drain, add cheap oil and more Rislone, run 5 minutes, drain. Then add good oil (10w30) and slick 50 with new good oil filter. In all cases, engine got better oil pressure, better gas mileage by at least 5%, better acceleration, less valve/lifter/engine noise, better everything. In my my 302, number 1 cylinder was only at 30% compression before and was at 87% after treatment and has held in the mid 80's for the last 60,000 miles. I only wish my tranny was as solid.

All engines are still running and doing great (some over 200k miles). When I bought my 98, the first thing I did was slick 50 it. If you go this route, make sure you re-treat every 25k with High Mileage Slick 50 - not just the booster. Good luck.

Just my $.02

I put in 5 quarts of Valvoline SAE 40 Racing oil, retains a higher viscosity at higher temps. I also put in LUCAS oil treatment, 1 quart.

Startup showed 60+psi and after running it hot and about 15 miles it held the oil pressure to the lowest running at 30psi.

Sitting at a light/stop sign it drops to about 15-20 I do not get a light, so it fixed that but the motor doesnt run the pressure of my Landlords 00 cherokee, or my brothers two chrokees. I guess we will see how it runs, ill try slick 50 at the next oil change, but as long as I get that stupid light to stop clicking on ill survive for now, I dont wan tto hear the girlfriend telling me "the light is coming on..."

You could always put tape over it....NO..not your girlfriends mouth....only kidding of course.