2005 Silverado oil pressure problems

[Sditt67]

I have a 2005 Chevrolet Silverado with a 5.3L with 239,xxx miles. I am experiencing oil pressure problems when the truck is cold and on an incline at idle. Twice now  I've had the warning on my display and the fast beeping alarm. As soon ss the truck is level it is fine. I've checked the oil and it's full. It has about 2500 miles on it since the last oil change. The oil pressure used to run 40-55 psi depending on temperature and rpm. It now sits at 30-35 psi until the truck is warmed up(approx. 10 mins) while driving before it runs at 40-55 psi. The second time that the oil pressure was low the valve train was very noisy so I don't think it's the gauge or sending unit. Any ideas? 

[diyer2]

History of this truck.

Oil change intervals?

Could motor have a sludge problem?.

Oil pump?

Easy, cheap remedy?

 

[Sditt67]

Oil change intervals of 4500-5000. 

[Sditt67]

Never had a pump but if it was the pump why would it only do it cold on an incline?

[diyer2]

I didn't mean did it have an oil pump change.

Pump going out?

I don't have the magic answer for you.

Sea Foam in the oil to clean out the motor is easy and cheap.

Why not try it?

 

[newdude]

Bad pickup tube o-ring?  Perhaps the pickup tube is coming loose/moving on inclines and unseating the seal.  Oil pressure that you are getting sounds totally normal.   

[Doug_Scott]

4 hours ago, Sditt67 said:

I have a 2005 Chevrolet Silverado with a 5.3L with 239,xxx miles. I am experiencing oil pressure problems when the truck is cold and on an incline at idle. Twice now  I've had the warning on my display and the fast beeping alarm. As soon ss the truck is level it is fine. I've checked the oil and it's full. It has about 2500 miles on it since the last oil change. The oil pressure used to run 40-55 psi depending on temperature and rpm. It now sits at 30-35 psi until the truck is warmed up(approx. 10 mins) while driving before it runs at 40-55 psi. The second time that the oil pressure was low the valve train was very noisy so I don't think it's the gauge or sending unit. Any ideas? 

When you say cold, what temperature are you saying?  Can you repeat this condition reliably?  You say it has happened twice now, have you parked the same way and not had this occur? 

[SunShine01]

Have you checked the accuracy of your gauges ?

Are your oil returns / oil pick ups sludged up ?

Is your oil pump working well ?

I remember years ago, in the GM 231 engines they had an external spring that assisted the oil pump. The spring would fatique you had oil pressure loss and lifters rapping. 2 bolt switch out on the side of the pan fix. So pumps do lose their ability to pump.


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[Sditt67]

4 hours ago, SunShine01 said:

Have you checked the accuracy of your gauges ?

Are your oil returns / oil pick ups sludged up ?

Is your oil pump working well ?

I remember years ago, in the GM 231 engines they had an external spring that assisted the oil pump. The spring would fatique you had oil pressure loss and lifters rapping. 2 bolt switch out on the side of the pan fix. So pumps do lose their ability to pump.


Sent from my iPhone using Tapatalk.                                                                                                       

 

 I don't think it's the gauge or sending unit. The 2nd time it did it the truck was on the incline running while I ran into a store. I was gone about 5 mins

 and when I come back the valve train was noisy and the low oil alarm was beeping and the gauge was at about 10psi. As soon as I backed up to level ground the pressure went up and the noise went away. The 1st time I was at at a stop light but only for about 15 seconds. The valve train wasnt starving for oil long enough to become noisy. As soon as I started moving to the pressure came back up.

 

 

[Sditt67]

Cold as in before the water temp is up to 210 which is where it always runs at. The first time was at a stop light briefly and the second time was for about 5 mins when I went into a store. The second time the valve train was noisy probably because it was starving for oil longer