Hi, My name is Max and I am new to this forum. Anyhow I have a situation and need some help. I have a 04 2500HD and noticed the other ...

Hi,

My name is Max and I am new to this forum. Anyhow I have a situation and need some help.

I have a 04 2500HD and noticed the other morning as I was leaving to work that my oil pressure needle was at zero and the readout said low oil pressure. Prior to noticing, I let the truck warm up for a few, went in the house for a bit, jumped in and took off. Got about two houses down the street and that's when I noticed the needle. I quickly shut the motor off, turned the key back on but did not start the motor just to see of the needle would jump, but no. I checked the oil level and it was fine so I tried to start the motor again - the needle was still at zero then it jumped up suddenly to normal presure. I drove to the end of the block turned around and parked it back in my driveway. Shut the motor off, let it set a bit then fired it up again and it did the same thing. The next day I changed the oil and it still did the same thing. Could it be a bad sending unit or is it the pump?

Any help would be greatly apriciated.

TIA
Max.

For me, I would first check the sending unit.
I had a pump go out on my car and it did all sorts of fun things to my engine.

Hi Max,
I would suspect that it's your sending unit. The gauge in my 2003 5.3L did the same thing about a year ago. I changed the sending unit and it has worked great ever since.

Its the instrument gage cluster, Chevys are natorious for that. My fuel guage works spontaniously along with my speedometer. If you checked the oil and it appears to be fine, I would bet money on it.

I have a question that has sparked tension and attitude. My 2004 silverado SS 6.0L lost oil pressure had 3 oil pumps installed one by myself not believing the dealer mec"s and nothing.. Please any suggestions​, I get 18 pis at best. sending unit seems fine and i have knocking sound of no pressure. is this what u have.

No not the cluster, already checked it and I have the engine knock to prove it...lol trust me I'm open to suggestions 107 k on her from day one Royal Purple ran.. Shop Mec's are really confused

yea, no thats not any instrument cluster. You said you already installed 3 different oil pumps? and each one independently failed or?

My truck had the same issue with the oil temp gauge, and my name is also max, lol

Ranger1223 wrote:I have a question that has sparked tension and attitude. My 2004 silverado SS 6.0L lost oil pressure had 3 oil pumps installed one by myself not believing the dealer mec"s and nothing.. Please any suggestions​, I get 18 pis at best. sending unit seems fine and i have knocking sound of no pressure. is this what u have.

Check the pump pickup for blockage. While the pan is off I would definatly check the bearings. Low oil pressure can be caused by bad bearings. If the engine is knocking, the bearings are probably bad now anyhow.

Mvs4 wrote:Hi,

My name is Max and I am new to this forum. Anyhow I have a situation and need some help.

I have a 04 2500HD and noticed the other morning as I was leaving to work that my oil pressure needle was at zero and the readout said low oil pressure. Prior to noticing, I let the truck warm up for a few, went in the house for a bit, jumped in and took off. Got about two houses down the street and that's when I noticed the needle. I quickly shut the motor off, turned the key back on but did not start the motor just to see of the needle would jump, but no. I checked the oil level and it was fine so I tried to start the motor again - the needle was still at zero then it jumped up suddenly to normal presure. I drove to the end of the block turned around and parked it back in my driveway. Shut the motor off, let it set a bit then fired it up again and it did the same thing. The next day I changed the oil and it still did the same thing. Could it be a bad sending unit or is it the pump?

Any help would be greatly apriciated.

TIA
Max.

It probably is a bad sending unit. I would, however, check the oil pressure with a mechanical gauge just to be sure. If it shows to be good by the mechanical gauge, put a new sensor in and that should fix it.