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Hello all, when I got my Comanche back on the road back in march and put ~20 miles on it before putting new oil in it. After that change, the oil pressure drops to less than 20 when warm. It has very little response to throttle and it makes a ticking (most likely valve/lifter) it has 60psi upon cold start and doesn’t tick when cold. Engine only has 126K on it. It doesn’t smoke and doesn’t have any other noises except for maybe one small exhaust leak and a EGR quack. I do not have a mechanical gauge to test actual oil pressure, and I can drop the oil pan if need be on a lift. in the video, most of the noise is from the countershaft bearing in the BA10/5. I’m eventually going to put an AX-15 in, I just haven’t got there yet, and thus, the noise persists. IMG_3079.MOV

Apologies on reviving an old thread. A month ago I took the oil pan off to replace the gasket and RMS. Doing so, I took the oil pump off to fully remove the oil pan from under the truck. Putting everything back together and starting the truck, I noticed the oil pressure gauge now sits at zero regardless of how long I’ve been driving it. I’ve replaced the sending unit. I’ve disconnected the wire, and the needle went far right, grounded the wire, and the needle went far left (0). I also took the sending unit off and stuck a zip-tie in to see if there was sludge build up, but nothing but clean, cold oil (after running it for 5 minutes). Could it be a bad oil pump? Just wanted to confirm and get input.

Hey. I just did a cluster swap on my 88 4.0 from dummy lights to gauges. So far everything is working fine except the oil pressure gauge. With the truck off, the gauge is at 40. When I'm moving, the gauge just goes up from there. Any ideas? Thanks.

I've searched a bit and found some threads discussing this but not any that quite answered my issue. So forgive me if there's one out there and I missed it. Also if y'all prefer me to resurrect and old thread instead of a new one, my apologies. So here's my situation... (I'm adding a bit of history to be sure I'm detailed for y'all) First I switched out the P.O.S. plastic valve cover with an aluminum one I snagged off a 4 banger XJ. Got the correct gasket and everything went well with the install. I did an oil change 10w30 Synthetic. I immediately noticed a loud tap on the top end just as I turned it over. Only a second, then gone. I thought it may be something with he fit. I asked A buddy and he said it just sounded like it took an extra second for the oil to catch up. So I changed the oil with Rotella 5w40 synthetic and the tap disappeared ... And now to the oil pressure... I swapped out my 89 pioneer dummy light cluster with a 90 XJ so I could finally get a temp, tach, and oil pressure reading. That also went relatively smoothly. I purchased (I believe) the correct switch for the pressure part #ECH OP6638 and swapped it with the old dummy sensor. My oil pressure read real high. No, not because the switch wasn't connected properly (I saw the spike to max b4 I had the switch installed). It was reading nearly 80 at startup and went down to 65~ at idle. Note: this was actually before I changed to the rotella t6. After the oil change it was ready maybe 70-75 at start up and around 55-60 at idle. When I accelerate its at 65-70. I actually was able to swap the switch for a new one at Napa expecting/hoping the switch was faulty. No luck. Same reading. I have a buddy that has a mech pressure gauge tester. To my delight, the gauge read 48-50 at idle and 60 when I gave it some gas. I was relieved to find out that my gauge runs 10 or so high. However that still seems a bit high, right? So after ready elsewhere it would seem that its above normal. But I wasn't sure if it was maybe any different with the 2.5L's. Maybe higher pressure with the smaller engine? IDK Would the gauges or switches read different in a 2.5L than a 4.0? Thanks in advance for your help! Oh and just to mention. I just broke 35k on this guy. Farm truck with low miles when I got it and it seems to be sealed up real well. No leaks that I can tell...

Sorry, but this is going to be a little long but I think I need to give some history. Back in the summer I helped a friend move a mattress and box spring. Nothing heavy. Now, he's about 300lbs. We were driving to his house and had been for about 30 minutes when I noticed that the truck was struggling a little to go up some hills. Nothing major, just over passes. I can't imagine that he would have caused that. Then I noticed that my oil pressure needle dropped to 0 and stayed there for a few seconds but the engine temp was normal as rain. I pulled over and checked the oil and yes, it was low. Maybe 3 quarts low. I added and went on our way. We got to his house and unloaded the mattress and box springs then when I started the truck and stepped on the brake it went completely to the floor. No pressure no nothing. I did notice that the engine compartment smelled a little like wire melting but I couldn't find anything wrong. I had the truck towed home. I came out the next day and the brake worked just fine and has ever since. What I've noticed since then is that my oil pressure seems lower than it used to be and that if I'm driving on the interstate at 65 to 70, after a while my oil pressure needle starts fluctuating all over the place. I check the oil and it's fine and the engine temp is fine. So, I'm thinking the pressure sending unit is bad. Yesterday, driving home and after only about 8 minutes of driving, the engine temp is creeping up. never actually gets in the red but right on the edge. 2 minutes later I'm home. In the driveway, I pop the radiator cap and add water until it's full. While the truck is sitting there idling, the temp needle gets a little into the red. I shut it down and let it sit over night. I check the oil level and it's fine. This morning while driving to work in about 35 degree weather, the engine temp gets hot fast and by the time I get to work, it's right at the edge of the red. Normally, since I only drive 3.5 miles to work, the engine would just barely even be warming up on a day like this before I got to work. The other thing I noticed this morning is that at one point, the heater stopped blowing hot air, the temp guage crept up some then the air turned hot again and the temp guage dropped just a tiny bit. The oil pressure was operating at about 40 psi while driving at 2500 rpms. At a stop, the oil pressure would drop to about 25psi. I've never heard the engine ticking even when my oil pressure needle dropped to 0. I do hear a slight ticking when I first start it in the morning but that only lasts about a second then it starts running quiet. I don't know if these two things are related. oh, when I popped the radiator cap in my driveway the water coming out was nice and rusty. this truck is a 91, 6 cyl, 4.0, 5speed 4wd with about 189K miles on it. I have no idea where to start to fix this. NEW: I just went down and was able to spin both cooling fans with the motor off. I'm thinking that should happen.

I just bought this 89 jeep comanche. Iran fine everything was good that I went to put a little bit of oil in it because the valve covers leaking gasket was leaking and I seen a little bit of milky oil in the rocker arm so I said oh no I've blown head gasket. so I check the oil no water on the dipstick. I'll pull one spark plug at a time to see if water comes out of the block as it turned over and that was a negative.put a new valve cover gasket on it, changed the oil, drove about 6 miles when I had a drop of oil pressure when I pulled up to a red light. I kept it going by having to keep my foot on the gas. It completely died out and the fuel pump quit entirely. Can someone please tell me what's going on?

I'm going to add Oil temp, Oil Pressure, water temp, AFR, trans temp, and some other gauges. Questions, Where is the best place to pull oil pressure? Near the factory one would be best, but I can't find any spliters for that. Water Temp, The engine is an HO from 92, and has a factory sensor up on the water neck. but, the old school temp sensor is still on the rear of the block. Can I replace that with a sensor from a gauge? I've looked hard, and and I can't find a "Deep" alum. Transmission pan for the Automatics in these trucks, do they make them? Those usually have a temp sensor hole. And, on the subject of Automatic Transmissions, what is everyone using for aftermarket cooling, that fits with the condenser? Thanks

so this has been an issue since ive gotten the truck only the tach and spedo and mabey the battery light work? the fuel gauge bounces around the temp gauge sits in the blue the oil pressure gauge is stuck over to the right? but just today i was going into town and a friend passed me and he called me asking why i was driving so slow ( my spedo said i was going 65) when i get to about an indicated 68mph the little pointer thing starts jumping around. also is 4000rpm normal for a 86 2.5 4x4 in 5th gear going 55-60? one thing i do know is that my tires are not stock size...i have 235/75/15 now wich replaced 215/75s but talking to the guy i bought it from said that those wernt stock size either he just took them off his xj and put them on the mj...i got the build sheet from the door jamb and under tires it says 6374 whatever that means? mabey this shouldve been split up into multiple post idk...anything would be great