5.3& 6.0 GM trucks losing oil pressure PF48E

Originally Posted By: 4WD
It’s a digital gauge transformed into analog “graphics” … oil pressure, fuel, temperature, charging
The tach and speedo have real needles …

At least we're getting something out of the new displays!

Patman: Yes, back in the day, they definitely had real gauges, in real time.
 
Originally Posted By: 4WD
Nice … your project?


Not mine, Built it for a customer.....He's scared to death of it, So it might be for sale in the Austin area.

He only had it built because he thought Rat-Rods are cool, He can't modulate the gas or brake pedal, It makes him so nervous he starts shaking.

I had a blast building it & it turned out perfect! The delivery process & trying to teach him to drive it will go down as one of the worst experiences of my career. He even threatened litigation on the premise it would drive like a brand new 2014 car.
 
Good grief … he must be from Austin
wink.gif
 
Originally Posted By: Garak
Incidentally, is GM still using real oil pressure gauges, or have they switched to dummies? It's been a lot of years for me with a new GM....


We routinely test our oil pressure with a real hand held gauge on our fleet trucks. The factory gauges have been accurate as far back as I remember. 2 new trucks on order so we'll see soon if the new ones are accurate.
 
Originally Posted By: clinebarger
Originally Posted By: 4WD
Nice … your project?


Not mine, Built it for a customer.....He's scared to death of it, So it might be for sale in the Austin area.

He only had it built because he thought Rat-Rods are cool, He can't modulate the gas or brake pedal, It makes him so nervous he starts shaking.

I had a blast building it & it turned out perfect! The delivery process & trying to teach him to drive it will go down as one of the worst experiences of my career. He even threatened litigation on the premise it would drive like a brand new 2014 car.



Originally Posted By: 4WD
Good grief … he must be from Austin
wink.gif



Good grief is right! Customer asks for it to be built this way but then threatens with litigation because it scares him.
crazy.gif

It's a crazy world we live in!
 
OK. Still no firm resolution on just what is going on here. I am going to quote from GMs SI #PIP5276D. For your information an S.I. is not a service bulletin but rather an internal document to dealers from GMs engineering. I am always surprised by how little of a problem Gm will delve into with their techs. More like the problem is on a need to know basis and you do not need to know.

Condition, "A concern of a P0521 setting after an oil change and or low oil pressure indicated on the instrument panel."

Recommendations, instructions. "If you are working on a Gen4 V8 that is setting a P0521 or and low oil pressure indicated on the instrument panel in cold or hot weather and the engine is currently equipped with a PF48E oil filter, replace with a UPF48R if one is available."

"Note: Only use the UPF48R if if the Gen.4 V8 is setting a DTCP0521." And I will note this line is in red on the S.I.

Will someone please tell me, why would you only go with the improved filter if you had a problem? If the filter is the problem why no just supersede it to a improved version? Just seems nonsensical. And just what is the core problem here? Is the problem with the filters inability to flow oil or the filters bypass valve? Or, is the problem with the engines oiling system?
 
One more log on the fire. I was reading in another forum that once the P0 521 for low oil pressure sets the gauge defaults to 0. If this is the case it would be a game changer. Would explain for why these trucks do not suffer any damage while running with 0 oil pressure, why the lifters do not rattle. Guess you are not going to know until you do some actual pressure testing on the vehicle.

The oil port on the back of the motor is difficult to get at, there is a adapter available to test the pressure by installing said adapter in place of the oil filter. Do not have one but will be getting one.
 
Originally Posted By: roygage
Recommendations, instructions. "If you are working on a Gen4 V8 that is setting a P0521 or and low oil pressure indicated on the instrument panel in cold or hot weather and the engine is currently equipped with a PF48E oil filter, replace with a UPF48R if one is available."

"Note: Only use the UPF48R if if the Gen.4 V8 is setting a DTCP0521." And I will note this line is in red on the S.I.

Will someone please tell me, why would you only go with the improved filter if you had a problem? If the filter is the problem why no just supersede it to a improved version? Just seems nonsensical. And just what is the core problem here? Is the problem with the filters inability to flow oil or the filters bypass valve? Or, is the problem with the engines oiling system?


The "R" in UPF48R usually denotes a "racing" filter and probably has a higher bypass valve setting. It probably also flows better, as I believe their UPF filters are synthetic media (they use to be anyway).

It's pretty hard to imagine it's a filter problem. But you do mention in your original post that this engine sounds pretty dirty and is plugging up filters rather quickly. If the filter's bypass valve is under sized it could cause oil flow restriction if the filter gets really plugged up, even when the bypass valve is opened. Simply putting on a new filter and seeing if the oil pressure comes back to normal would say that the old (clogged?) filter is at fault. If a new filter doesn't restore oil pressure then the problem is not the filter.

As you mentioned above, definately use an accurate mechanical pressure gauge to verify the oil pump is heathy.
 
Well some more real world info on this problem. I was driving out of town this morning and noticed the oil pressure was dipping below 10 psi. I put it in neutral and gave it some revs and it popped up to around 30 for a second so the gauge seemed to be doing something. Then it started dipping lower until the warning came on. I pulled over and left it running and the engine sounded fine even with the gauge at 0. I turned it on and off a few times and it came back up to around 35. I decided to continue to my destination since I was halfway there. The gauge settled on about 10 psi for the rest of the trip(about 40 more miles).

After my meeting pressure came up to 40 idle cold and stayed at its normal 38 psi at 1750 rpm on the highway for the way home. I am not thinking it is the filter anymore and likely some gunk plugging the screen at the sensor or at least I hope. Our shop mechanic things that is the case - he said if it were the o-ring and it was pumping air at 0 psi the lifters would have been clattering something terrible.

This is with a Wix 57060 and 5w30 dexos with about 4000 miles on it.

2010 5.3 chevy
 
Originally Posted By: cmlind
Well some more real world info on this problem. I was driving out of town this morning and noticed the oil pressure was dipping below 10 psi. I put it in neutral and gave it some revs and it popped up to around 30 for a second so the gauge seemed to be doing something. Then it started dipping lower until the warning came on. I pulled over and left it running and the engine sounded fine even with the gauge at 0. I turned it on and off a few times and it came back up to around 35. I decided to continue to my destination since I was halfway there. The gauge settled on about 10 psi for the rest of the trip(about 40 more miles).

After my meeting pressure came up to 40 idle cold and stayed at its normal 38 psi at 1750 rpm on the highway for the way home. I am not thinking it is the filter anymore and likely some gunk plugging the screen at the sensor or at least I hope. Our shop mechanic things that is the case - he said if it were the o-ring and it was pumping air at 0 psi the lifters would have been clattering something terrible.

This is with a Wix 57060 and 5w30 dexos with about 4000 miles on it.

2010 5.3 chevy

I am curious what your driving conditions and habits are? Also OCI and FCI habits?
 
I have changed the oil with around 30% left most times (5-7k) but switched from semisyn to Dexos 2 years and 30k ago and did go to 0% a couple times - 10k miles.

Most of my driving is at least 10 mile trips with a fair amount of highway miles. I do have some idling and 4000 lb trailer hauling. It is a work truck but mostly just moving me to jobs sites with the occasional hauling.
 
Originally Posted By: WellOiled
Originally Posted By: cmlind
Well some more real world info on this problem. I was driving out of town this morning and noticed the oil pressure was dipping below 10 psi. I put it in neutral and gave it some revs and it popped up to around 30 for a second so the gauge seemed to be doing something. Then it started dipping lower until the warning came on. I pulled over and left it running and the engine sounded fine even with the gauge at 0. I turned it on and off a few times and it came back up to around 35. I decided to continue to my destination since I was halfway there. The gauge settled on about 10 psi for the rest of the trip(about 40 more miles).

After my meeting pressure came up to 40 idle cold and stayed at its normal 38 psi at 1750 rpm on the highway for the way home. I am not thinking it is the filter anymore and likely some gunk plugging the screen at the sensor or at least I hope. Our shop mechanic things that is the case - he said if it were the o-ring and it was pumping air at 0 psi the lifters would have been clattering something terrible.

This is with a Wix 57060 and 5w30 dexos with about 4000 miles on it.

2010 5.3 chevy

I am curious what your driving conditions and habits are? Also OCI and FCI habits?


I’d vote change the oil and filter or if you are convinced it’s just the filter, change it first to be scientific. Check it, then change the oil and check it.
 
Originally Posted By: roygage
One more log on the fire. I was reading in another forum that once the P0 521 for low oil pressure sets the gauge defaults to 0. If this is the case it would be a game changer. Would explain for why these trucks do not suffer any damage while running with 0 oil pressure, why the lifters do not rattle. Guess you are not going to know until you do some actual pressure testing on the vehicle.

The oil port on the back of the motor is difficult to get at, there is a adapter available to test the pressure by installing said adapter in place of the oil filter. Do not have one but will be getting one.


The times I have ran across a P0521, The gauge follows whatever voltage the PCM receives from the EOP sensor.

You can make your own testing adapter from a Gen III oil cooler bypass plate as it has a bung/boss unlike the Gen IV bypass plate, This will give you pressure right after the filter. Just drill out the bung & tap it to 1/8" NPT.

7uPpoFe.jpg
 
Originally Posted By: WellOiled
Originally Posted By: cmlind
But I had the same thing happen on my work truck. I changed the PF48E to a Wix 57060 and fresh oil and all has been well for around 4000 miles. '10 5.3 with 127k. Still watching it to see if it is the o-ring. Not sure how a filter can do that, but in my case it does appear to be the filter also. I have changed the oil with around 30% left most times (5-7k) but switched from semisyn to Dexos 2 years and 30k ago and did go to 0% a couple times - 10k miles.


Originally Posted By: cmlind
Well some more real world info on this problem. I was driving out of town this morning and noticed the oil pressure was dipping below 10 psi. I put it in neutral and gave it some revs and it popped up to around 30 for a second so the gauge seemed to be doing something. Then it started dipping lower until the warning came on. I pulled over and left it running and the engine sounded fine even with the gauge at 0. I turned it on and off a few times and it came back up to around 35. I decided to continue to my destination since I was halfway there. The gauge settled on about 10 psi for the rest of the trip(about 40 more miles).

After my meeting pressure came up to 40 idle cold and stayed at its normal 38 psi at 1750 rpm on the highway for the way home. I am not thinking it is the filter anymore and likely some gunk plugging the screen at the sensor or at least I hope. Our shop mechanic things that is the case - he said if it were the o-ring and it was pumping air at 0 psi the lifters would have been clattering something terrible.

This is with a Wix 57060 and 5w30 dexos with about 4000 miles on it.

2010 5.3 chevy

It appears you have had this happen at least twice and the “cure” was an oil and filter change at 4000 miles when the symptoms manifest.

I suspect the filters are full and on the edge of bypass when this happens. A full synthetic filter would provide more capacity in the same physical size and may give you a better margin before this happens again.

I think the oil pressure sensor screen may have to be replaced. If you go that far, it might make sense to change the oil pressure sensor at the same time in case it is intermittent.

The OLM appears to be very basic and not conservative enough for your conditions. I would lean toward the short OCI / FCI you have done.
 
That was the theory. Then why has it resolved itself this time without a change? I likely will change the oil soon, but am not sure if that really solved the problem or if it is intermittent on it's own.
 
Problem #1. Somehow the passage leading to the oil pressure sensor is not a stay clean design. It needs help through mechanical cleaning. Changing the oil and filter may not clean this area sufficiently by itself.

Problem #2. The oil pressure sensor may be intermittent. Moisture can enter the gauge from the electrical connections. This moisture can degrade the bridge in the sensor. The sensor can be irratic depending on the amount of moisture.
 
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