Oil Pressure

[DogramTD]

On start-up, the oil pressure will drop to zero after about 5 seconds. I cannot find any pattern to this except for that it usually happens (randomly)in the mornings. It will drop to zero and the check guages light will come on. If I immediately shut it down and restart it, it is fine. Unfortunately, there are times where I will just reachover to start the truck and walk away while it warms up. If the pressure drops off I can tell because it will sound a bit more chattery than usual, at that point i'll walk back to the truck and sure enogh, it has dropped to zero.



I have brought the truck in to the dealership 3 times for this (under warranty), one of the times they kept it for a week. They have replaced the oil cooler (thinking it was a stuck check valve) and they have replaced the sending unit 2 times. Nothing has fixed it and now they wont touch it unless I pay because the warranty has expired.



Has anyone experienced this and can tell me what is going on? I would think its just an electronic issue but I can hear the lack of oil pressure in the motor when it happens. HELP!#@$%!

 

[BHanna]

I'd think you could convince someone higher up to reconsider fixing it under warranty. If the problem was identified before the warranty ran out but the dealer wasn't able to fix it, they should honor the warranty. You may have to keep asking to speak to people's bosses but eventually you'll probably get to someone with some common sense. If that has happened enough times, you may have some engine damage and they may need to tear it apart to see what's going on inside.

 

[MShaheen]

if the problem persisted during the warranty period and the dealer failed to fix, they are required to fix the problem. It does not matter if it is expired or not.

 

[RKerner]

What year truck? How many miles? Any aftermarket oil filtration systems? My truck experienced no oil pressure once and I removed the remote filter system and replaced it with just a single bypass filter. If you have no remote filter system, then the oil pump may be losing its prime or the pickup is not functioning properly (cracked, plugged)

 

[DogramTD]

05' w/49K miles. Stock oil filtration system. As far as the warranty, I said the same things that you all are. They told me that chrysler would have to look at the history and make that decision, not the dealer. They wanted to flash my ECM, I was reluctant to let them do that since I was told it would turn the pressure guage into a dummy light, reading 40 PSI no matter the pressure unless it dropped to zero. Needless to say, I declined the flash.



Thats a good point about the pump loosing prime, didnt think about that.

 

[JDKammin]

Did they ever hook up a mechanical gauge to watch the oil pressure?

 

[AH64ID]

05' w/49K miles. Stock oil filtration system. As far as the warranty, I said the same things that you all are. They told me that chrysler would have to look at the history and make that decision, not the dealer. They wanted to flash my ECM, I was reluctant to let them do that since I was told it would turn the pressure guage into a dummy light, reading 40 PSI no matter the pressure unless it dropped to zero. Needless to say, I declined the flash.



Thats a good point about the pump loosing prime, didnt think about that.

The oil psi gauge is already an idiot gauge. The sender is a pressure switch not a pressure transducer. So all the ECM knows is if there is 6psi or not. The stock gauge is really only accurate from about 1200-1400 rpms (I have a mech gauge)



You should be able to get it covered under warranty. . and 05 has a 7/70 powertrain and a 100K Cummins warranty. Your dealership is being stupid. . they should be trying to help you so they can make money.

 

[WHazelwood]

I've had the same thing happen a couple of time when parked on an incline nose up. Pressure will drop and before the needle hits the bottom it will start to come up again. It'll give me the warning chime but the pressure is already going back up by then. I've got 88K on the odometer and the truck runs great.

 

[DogramTD]

Did they ever hook up a mechanical gauge to watch the oil pressure?

They did, but it never reproduced so it didnt do much good.

 

[DogramTD]

I've had the same thing happen a couple of time when parked on an incline nose up. Pressure will drop and before the needle hits the bottom it will start to come up again. It'll give me the warning chime but the pressure is already going back up by then. I've got 88K on the odometer and the truck runs great.

Mine will actually be fine for the first 5-10 seconds then it drops like a rock to 0 and the check guages light comes on. Never comes back up unless I shut it down and restart it. It has actually happened before as I was driving away (in a neighborhood at about 10 MPH)



In fact, it happened again this morning!

 

[AH64ID]

Mine will actually be fine for the first 5-10 seconds then it drops like a rock to 0 and the check guages light comes on. Never comes back up unless I shut it down and restart it. It has actually happened before as I was driving away (in a neighborhood at about 10 MPH)



In fact, it happened again this morning!

That sounds like a sender(switch)... . or your out of oil.

 

[DogramTD]

That sounds like a sender(switch)... . or your out of oil.

LOL! ok... quick disclaimer, I do have extensive mechanical experience, notprofessional, but extensive. This is mainly in gas motors though, so thats why I ask you guys. I am picking up on this diesel stuff and hoping to learn others experiences.



So, yes there is oil in it! LoL! and the dealership has replaced the sender 2 times. The motor physically sounds a bit more chattery when the oil pressure drops off, this is why I think it is ACTUALLY loosing pressure.



It seems like I am the only one with this issue so far. #@$%!

 

[AH64ID]

LOL! ok... quick disclaimer, I do have extensive mechanical experience, notprofessional, but extensive. This is mainly in gas motors though, so thats why I ask you guys. I am picking up on this diesel stuff and hoping to learn others experiences.



So, yes there is oil in it! LoL! and the dealership has replaced the sender 2 times. The motor physically sounds a bit more chattery when the oil pressure drops off, this is why I think it is ACTUALLY loosing pressure.



It seems like I am the only one with this issue so far. #@$%!

Then I am not sure what to tell you. . maybe an oil pressure gauge would help you diagnose...



Thats the thing about oil pumps, they are purely mechanical. . and generally work or don't work. . unless you have a faulty bypass valve.

 

[jelag]

We've had this happen but the truck never really lost oil pressure... a test proved that the pump was working ... we pulled off all the connectors, cleaned them and re-installed them and never had a problem...

I don't remember seeing an in warranty truck with with an oil pump problem...

Just my thoughts... .

 

[BHanna]

This is just a wild guess but a chunk of something floating in the oil pan could be blocking the pickup sometimes and not others. Of course, you'd probably expect the pressure to go to 0 driving down the road once in a while too.

 

[DogramTD]

Is the oil pump in this motor just like gassers, drop the pan and unbolt the pump? Will the pan drop w/o jacking the motor up?

 

[Redmega06]

Ok I just had motor rebuilt and I started it and let it idle a little while and had the pressure drop to zero. I can shut it off and restart and the oil pressure is fine. I never had this problem before. I do not hear anything different.

 

[Redmega06]

Well I replaced the oil pressure switch last night and drove it a little while. I let it idle and went through several restarts with a couple of short trips and so far so good.

 

[DogramTD]

Hey all, thought I'd revisit this post since I am STILL having the same problem.



Just posted the following in the Cumminsforum site it was a response to someone else, who finally, has experienced the same thing I am...



Let me add this is not just an '03 issue, i too have the same issue of which I have posted here and TDR; no luck. Mine started at around 36K miles; its been to the stealership 3 times for it. They have replaced the Oil PRV, flashed the ECM, replaced the sending unit... no luck. I started running FG filters and noticed the problem went away for awhile; it has returned! It used to only occur occasionlly on morning start up, didnt matter what the temp was or even if I had just changed the oil or it was 3K miles old. I have always ran Valvoline 15-40 premium Blue oil in it. Everytime it would happen I IMMEDIATELY shut it down. I didnt let it run or rev it... Bad Idea! I would restart it and pressure would come right back as usual. Sometimes it would only take 1 shut down/start up cycle, other times i might have to cycle it 2-3 times. Well now it has gotten far too frequent and at times have to start and stop it 5 or more times before the pressure holds; once it holds, its good for the rest of the day. I just ordered a manual gauge and will start my own trouble shooting when I get home from this trip i am on.



If in fact I am losing pressure and its not just an electrical or ECM glitch (I do think the OP is dropping off because there is a noticable difference in the mechanical sound of the motor) the only place I can see, IAW the manual, where I may be having a problem is the oil cooler. A gear pump is a positive displacement pump and wont just lose prime or work intermittently (from my experiences and training as a water distro craftsman). If need be I will throw a part at it and it will be the oil cooler; at only $80 its worth it.



Glad to hear someone else is experiencing this; not because misery loves company but rather I have others to work with as we navigate out of this mess!



Here is the link to that thread might you have any interest in reading it...



No Oil Pressure & Can't locate Oil Pressure Relief Valve - Dodge Cummins Diesel Forum

 

[BIGNASTY]

I dont think I would go there JMO :-laf