Guys, chime in

[02 Silverado Z71]

Hey fellas, go a question for ya.

My truck, when engine idling, in Drive, will register an oil pressure just a bit *under* 40 psi. If I had to take a stab at it, I would say around 37-38 psi.

 

Normal?? I always thought the newer Generation 3 engines had much higher oil pressure when compared to the old 5.7 lietr V8.

 

My truck is an 04 Sierra 1500 Z71 SLT, with only 5600 miles on it. It has already had 2 or 3 oil changes with conventional oil.

 

Is my oil pressure a little low? My old 02 Silverado with a 5.3 always read a bit higher on the dash.

 

On the '04 - no engine noises at all.

[facn8me]

Sounds normal to me.

[ericag02]

Sounds like my truck, '04 1500 Silverado 5.3...Hit the gas the Oil Pressure will go up some, but idling it will be hanging out around 40 or so.

[Jansen]

2004 Sierra Z71 with 5.3L and 21000 miles. When at idle, my oil pressure is 40psi. I think your truck is normal.

 

Jansen

[02 Silverado Z71]

Thanks for the replies fellas...just curious about that issue.

[Ben]

First....note that any OEM dash gauge(s) are not very accurate, except for the

speedo (that is mandated by law as to the min accuracy). Best used to

determind trends and genearl health based on it being "normal" or not.

 

My 1980 Silverado C10's 5.7L was rebuilt in the early-mid 90's. "Built" with

ported, flowed, matched, CC'd and polished heads. Low rev'ing torquer

cam, rocker/springs and stainless valves, etc. Ditto work on the block &

tranny. Edelbrock Performer intake manifold & carb.

 

It now has over 100K miles on that engine. The oil pressure gauge is

a "direct", meaning an oil line goes to the gauge and idle is a tad over

40psi and over 1000 rpms pegs the gauge over 60 PSI.

 

My 1996 Suburban 7.4L is a ditto.

 

So, what I'm saying is that it depends on what state of engine build, tune

and care (materials and schedule). Get to know "your" vehicle and how

it performs and what the gauges indicate when new. Then constantly check

them for changes. You can tell lots just by how they act.

 

I know to change engine oil when the pressure drops and oil consumption

starts. I've changed out a fresh charge of Mobil 1 oil and filter after about

500 miles towing ***HARD***. Knew I cooked the engine oil because

the pressure dropped a few and it started to consume oil. Changed it

and it went back to normal and stopped consuming.

 

Here's some pictures of them both: