I don't know. I'm pretty sure my oil pressure used to be 40psi at idle when warm. Now it's like 30. When cruising around 2500rpms it's about 45-50psi. Should I be worried? Maybe just bad sensor or something? It's a completely stock 04 5.3. Just started noticing it was a tad lower than it used to be probably around 7,000 miles ago. I might just be paranoid.

 

How many miles on the engine and what weight oil are you using? My 02 5.3 runs about 45psi warm at idle and about 60psi on the highway. Truck has 145K on it and I use 5w30 Valvoline Synthetic.

 

I noticed mine is running lower than normal also. Im runing Delo 400 15w40 and its 40 at 750rpm idle. When its 100* outside and i idle for a lil while it will go down to 35 which still doesnt bother me.

But at 2000rpms its been 60psi for as long as ive driven this truck since 2004. But now it hangs out at 45-50psi at 2000.

 

engine only has 95k miles. 5w-30 mobil 1 oil. i'm just a little worried something internal is not right

 

No odd noises or anything?

 

nothing, runs like a champ. I was planning on putting a turbo on it in a couple weeks, but I don't really want to if I don't know what's going on with the oil pressure...

 

The main thing to worry about, at least in my mind anyway, is if the pressure doesnt go up when you accelerate. As long as it holds steady at idle and increases as you accelerate then the pump is doing its job correctly.

That being said, if it was higher before then that can only mean tolerances have increased, whether in the oil pump itself or in the motor (main bearings, rod bearings, cam bearings, etc.) it is hard to say.

One thing you could try that is free and easy is next time you change the oil, cut the filter open and see if you see any copper colored material in it. If so that is bearing material and likely the loss of oil pressure is due to wear in the bearings (cam, main, rod).

 

Yea that's what I'm worried about, but I don't even beat on it that much haha. It's fine other than being just about maybe 5-10psi lower everywhere in cruising RPMs