Suggestions about Oil Pressure on a 2004 4X4 Silverado

[jimmer]

Just going to throw this out there and maybe get some pointers. I have owned this truck for 3 years. Had the oil pressure warning go off at idle the first summer I owned it. I changed out the oil pressure sensor and changed the oil. It solved the problem to some degree. That warning would go off again at around 5000 km after the oil change.  I would change the oil and again solve the problem of the warning sound going off, the pressure seemed to read low at idle still, but no sound. Recently the oil change would not solve it and the warning sound was going off at 40 km/hr. There is no knocking or noisy lifters coming from the engine at idle. I had brought it in to get checked and it was determined that the pressure is dropping after a manual pressure test with a gauge. So, $560 later I know the pressure is dropping at idle and they wired the sensor to trick it so the warning sound wouldn't drive me crazy. That was another brand new sensor installed from GM (I had just replaced the senor with an aftermarket one). They put in 15w40, which I have since changed out (wasn't comfortable with the thick oil in the cold) and added a bottle of Lucas. I have thoughts that the o-ring on the oil pick going into the pump up might be a problem, but they want $1500 to drop the oil pan and replace the pick up and o-ring. I would do this myself, except for the fact that the front diff has to be loosened to drop the pan. Tough when laying on my back at my age. It was suggested that I just put in a used running engine for approximately $3000. One of my concerns is that I replace the engine and then the tranny goes. I am rambling a bit, sorry. So, one of my questions is, shouldn't I be hearing noise from the engine if the engine is breaking down? The truck is in great shape for it's age and it has 360,000 on the Vortec 5.3.  Any suggestions, tips, pointers or past experiences would be appreciated. I feel like I'm driving on borrowed time.

Thanks Jimmer

Edited December 10, 2018 by jimmer

[OhioFisherman]

No idea if that is your problem, but it seems to be one?

 

[jimmer]

10 minutes ago, OhioFisherman said:

No idea if that is your problem, but it seems to be one?

 

I did look at that video Ohio, thanks.

[Fisherman]

Like you said you don't want to throw money in a bottomless pit.  My neighbour replaced his motor last spring and within short time, in no particular order other things started going south.  I wonder how much sludge is in the engine keeping the oil from flowing properly.  That was his problem but he waited too long and it just plain quit.  I'm a fan of real synthetic oils,  never had an issue with it.

[aplumma]

You are showing all of the signs of a worn out oil delivery system. This could be due to a leak or the pump is going bad. The reason the thicker oil is allowing the sensor to be quiet is it is creating back pressure between the pump and the sensor. This is usual for a high wear on the pump situation. The mechanics are correct  that is the issue and the noises you expect are the damage done after a low pressure has allowed excessive wear on the motor. You can either run it till it blows up and replace the engine or replace it before it blows up but it is going to blow at some place or time. If you have a second vehicle or if it blows it will not be stressful then let it eat. If you travel in it and it is the only car then consider repairing it or replacing it at your convenience. With high mileage vehicle I hesitate to replace major components when the rest of the vehicle is the same age. 

Good luck

Art

[jimmer]

1 hour ago, aplumma said:

You are showing all of the signs of a worn out oil delivery system. This could be due to a leak or the pump is going bad. The reason the thicker oil is allowing the sensor to be quiet is it is creating back pressure between the pump and the sensor. This is usual for a high wear on the pump situation. The mechanics are correct  that is the issue and the noises you expect are the damage done after a low pressure has allowed excessive wear on the motor. You can either run it till it blows up and replace the engine or replace it before it blows up but it is going to blow at some place or time. If you have a second vehicle or if it blows it will not be stressful then let it eat. If you travel in it and it is the only car then consider repairing it or replacing it at your convenience. With high mileage vehicle I hesitate to replace major components when the rest of the vehicle is the same age. 

Good luck

Art

The mechanic actually wired in some diodes to trick the sensor into thinking that the volts aren't dropping to the voltage that triggers the warning sound.  It's such a shame because it's evident that the vehicle was cared for and maintained well (other than this). I have never seen any sludge during oil changes, even when I cleaned it with seafoam (not to say that there isn't an internal issue like Fisherman indicated). Everyone that has worked on the vehicle comments on the good condition. I do agree with you on the worn out oil delivery system aplumma.   All too much for me to do, maybe I can find someone to drop the oil pan for less and try the simple fix of the o-ring.

Replacing the vehicle is obviously the best option and I will be looking into that also.

I appreciate the responses, thanks!

[Old Ironmaker]

Low oil pressure is something I thought went away with modern engines. I don't even check the oil anymore between oil and filter changes. 2003. You are going to throw good money after bad. You have a 16 year old truck, time for a newer truck I'm sorry to say, or live with it and change that oil every 5K. I'd live with it until the tranny dies. I have driven early 2000 vehicles into the scrap yard that look great. Usually it was computer related or tranny related problems, the engines ran like a clock. 1998 Pontiac Grand Prix with 350,000 kms, a 2002 Dodge Intrepid with 340,000 kms and a 07' Nissan Altima with 390,000 kms. The Pontiac was rusty but the other 2 looked great but I wasn't about to spend 1000's to keep them on the road waiting for something else to go.

I forgot my 89' GMC Sierra step side. The odometer stopped at 500,000 kms. It's still on the road, I gave it to my 18 year old nephew 7 years ago. I'd drive it into the ground if it were me. Put a piece of electrical tape over the red alarm and disconnect the ding, ding.  

Edited December 11, 2018 by Old Ironmaker

[OhioFisherman]

Jimmer, if I was going to pay for someone to drop the pan on that vehicle to replace an o ring I would probably pay the couple hundred bucks for a new oil pump too.  You really don't want to have to do it more than once?

Engine noise, you would probably hear lifter and valve train noise before you hear bearing noise like from crank or camshaft bearing, but by the time you do hear the noise from them it is already too late.

[Old Ironmaker]

One may ask how can you get that many K's on more than 1 vehicle. I had sales guys driving them at any given time. Our territory went from Niagara to Oshawa and Port Huron to northern Detroit where our supplier was and back. It adds up. 

[canoecarrier]

I had an oil pressure issue also, when the engine would get hot the light would start blinking. It was a good feeling when you were way out in the bush lol ! 

I took it to a dealer, and they basically told to me to get rid of it. With 350,000 on it, and problems piling up , that is a money pit.

 

Get rid of it before you put more money into it and then buying a new vehicle anyway because it left you stranded, both in your wallet and on the side of the road!!

 

Run while you still can !! 

[jimmer]

14 hours ago, OhioFisherman said:

Jimmer, if I was going to pay for someone to drop the pan on that vehicle to replace an o ring I would probably pay the couple hundred bucks for a new oil pump too.  You really don't want to have to do it more than once?

Engine noise, you would probably hear lifter and valve train noise before you hear bearing noise like from crank or camshaft bearing, but by the time you do hear the noise from them it is already too late.

Unfortunately, I don't think the oil pump can be changed through the oil pan. It sits in front of the timing chain.

I think I am going to cross my fingers that it lasts a while and start looking for another vehicle.

[Whitespinnerbait]

I would switch to a 15w40 oil and keep driving.....why not ??

[DanD]

This is a long shot; but it has helped with a number of these high mileage GM engines. Go to Crappy Tire and get a bottle of the Lucas engine oil stop leak.

Lucas

This stuff will soften and swell rubber seals and if it is the pick-up tube seal (Which it likely is; I have done lots of them) you may get lucky and seal up the suction tube? It won't hurt anything, Lucas products have served me and my customer's vehicle's well over the years. Change the oil again and then pour this stuff in; even with the 15W40; diesel engines run it year round; so it wont hurt a 360K loosey goosey gas engine. LOL Take the truck for a drive (an hour or so) that'll give this stuff a chance to work through the whole lubrication system and have a chance to do its job.

Dan.

[jimmer]

7 minutes ago, DanD said:

This is a long shot; but it has helped with a number of these high mileage GM engines. Go to Crappy Tire and get a bottle of the Lucas engine oil stop leak.

Lucas

This stuff will soften and swell rubber seals and if it is the pick-up tube seal (Which it likely is; I have done lots of them) you may get lucky and seal up the suction tube? It won't hurt anything, Lucas products have served me and my customer's vehicle's well over the years. Change the oil again and then pour this stuff in; even with the 15W40; diesel engines run it year round; so it wont hurt a 360K loosey goosey gas engine. LOL Take the truck for a drive (an hour or so) that'll give this stuff a chance to work through the whole lubrication system and have a chance to do its job.

Dan.

Geez, I just put in a bottle of Lucas Oil Stabilizer on the weekend. Do you mind if I ask the going rate should be to drop the oil pan in this vehicle?

[DanD]

Flat rate book pays 3 hours on a 4X4; so depending on the shop's rate and or other issues; as in seized differential mounting bolts or bad U or CV joints, could all add to the cost?

The oil pan gasket is around a 100 bucks; the pick up tube seal is about 6 bucks, then an oil filter and fresh oil; add another 40.  I'm also going to say that this seal change is not a guarantee; you've got a 50/50 chance that it is the actual problem? So I guess I'm saying throw the dice and hope like hell you don't roll snake eyes?

Dan.

[jimmer]

Thanks DanD.  That's not as bad as I thought.  Someone quoted me $1500, might ask around now.

I'm actually keeping my eyes open for another truck also.

[Old Ironmaker]

Drive it until it dies. I wouldn't even put the 5 or 6 hundred bucks into it even if it was better than a 50/50 chance that's the problem. 

[cisco]

I'd go to NAPA and ask who they'd recommend to do it for cash. Lots of backyard guys with garages to do it for much less than dealer or other expensive wrenches.

I've been told rubber nowadays has lots of vinyl in it. This is what we get, cracking and breaking/ loss of flexibility.

You've already got $560. into it. To sell the truck with low oil pressure means you're either going to fool someone or you are going to take a big hit on resale value. 

Oh and I drove a few old vehicles and Dura Lube helped them all last/stop passing oil quite a bit.   

Be thankful for Youtube for the advice that looks so promising. $1500. even sounds good at 350,000km..

If you just drive it til it drops you'll constantly be thinking and worrying about the problem. When will it happen? Where will you be stranded with a scrap truck? 

Better to get the seal replaced. Either it is fixed or you know you've tried. 

Edited December 11, 2018 by cisco

[jimmer]

14 hours ago, cisco said:

I'd go to NAPA and ask who they'd recommend to do it for cash. Lots of backyard guys with garages to do it for much less than dealer or other expensive wrenches.

I've been told rubber nowadays has lots of vinyl in it. This is what we get, cracking and breaking/ loss of flexibility.

You've already got $560. into it. To sell the truck with low oil pressure means you're either going to fool someone or you are going to take a big hit on resale value. 

Oh and I drove a few old vehicles and Dura Lube helped them all last/stop passing oil quite a bit.   

Be thankful for Youtube for the advice that looks so promising. $1500. even sounds good at 350,000km..

If you just drive it til it drops you'll constantly be thinking and worrying about the problem. When will it happen? Where will you be stranded with a scrap truck? 

Better to get the seal replaced. Either it is fixed or you know you've tried. 

I hear you about being stranded, but still a struggle to put the money out.

[GBW]

PM me Jimmer if you want me to see if a Lindsay local (Chevy guy) can give you a look over and or hand if you want to put a little $$ in to take a chance.  

Edited December 12, 2018 by GBW

[Old Ironmaker]

9 hours ago, jimmer said:

I hear you about being stranded, but still a struggle to put the money out.

The best 100 bucks someone driving an old vehicle can spend is on a CAA membership. Don't leave home without it. 

[ecmilley]

Easy enough to drop the pan in driveway done it.for several friends 1 bad o ring 2 sludged pick ups . And usually.all the.additives just reliquify sludge and move it into pick up

[porkpie]

Every time I have to put $1500 into a vehicle, I consider that it's only about 3 months of car payments.  Maybe less.  So if I only get 3 more months out of the vehicle, I'm really not that far behind.  Last year I had replaced the suspension and steering components within a year as well as bought some new snows for my 2005 SUV.  Then some dummy rearended me at a stop light and wrote it off for me!  That hurt.  Wife was happy that she got a new SUV though.  I was not, as I had intended to drive it for a couple more years.  So if your a gambler just consider what car/truck payments might be and decide if it's worth it to do the work.  You may drive it for a couple more years, but it's always a gamble.

[Headhunter]

I suggest that you leave the truck running/warming up in your driveway and go in the house to "grab a few things" while it's warming. With any luck, it will be gone when you come out.

Sorry, that's the best I could come up with!

HH

[jimmer]

59 minutes ago, Headhunter said:

I suggest that you leave the truck running/warming up in your driveway and go in the house to "grab a few things" while it's warming. With any luck, it will be gone when you come out.

Sorry, that's the best I could come up with!

HH

I doubt that would happen where I live.