Oil pressure Concern (1 Viewer)

[JB Mitchell]

Realizing that there’s going to be some variation in gauges - I’ve got a concern about my oil pressure reading. Warm, my idle oil pressure reads just below the first line (1/4) and my cruising (roughly 2500 rpm) just shy of the second line (1/2). At higher RPMs it will go closer to the third line, where it also goes when the oil is cold. Unfortunately, because I have several vehicles, I don’t remember if it’s always been this way. I just noticed recently how low the idle dropped and it seemed wrong. Note: it’s had a recent oil change with the correct viscosity. Does it seem like there might be a problem here?

 

[abuck99]

Normal

 

[Trunk Monkey]

 

[JunkCrzr89]

 

[lehiguy]

If you are really concerned and/or curious, you could remove the sending unit and thread in an actual gauge and see what you have. Typically (this is my old-school, SBC data bank here) you want 10 psi per 1000 RPM. So 20 PSI at 2000 RPM, 50 PSI at 5000 RPM, etc.

 

[Hokie99]

Realizing that there’s going to be some variation in gauges - I’ve got a concern about my oil pressure reading. Warm, my idle oil pressure reads just below the first line (1/4) and my cruising (roughly 2500 rpm) just shy of the second line (1/2). At higher RPMs it will go closer to the third line, where it also goes when the oil is cold. Unfortunately, because I have several vehicles, I don’t remember if it’s always been this way. I just noticed recently how low the idle dropped and it seemed wrong. Note: it’s had a recent oil change with the correct viscosity. Does it seem like there might be a problem here?

These 4.7s are notorious for having oil pressure gauges that read “low” especially as they age.

These engines also require very little oil pressure at idle, if I remember something like 5psi and they will survive for along time.

For what’s its worth one of my kids 100 series reads just like yours.

But.... I just changed the oil to Amsoil and a Wix filter on my other 100 series and wouldn’t you know the oil pressure is up across the board. Who knows, just my. 2 cents

 

[Smiles]

Normal

Plus 1

 

[thebeedeegee]

Mine is like this. Going 55 to 60 yesterday it was around halfway on the gauge. Idle is just over 1/4 or so

 

[Hokie99]

To follow up on, it does seem that once all of my LC 100’s once they have 2500 miles or so on an oil change the oil pressure at idle when the engine is warmed up seems to be very low at idle and in drive, but with a fresh oil change the pressure is definitely higher on the gauge at idle and engine warmed up. Both of my 100s have approx 250k miles that do not eat oil and have good power.

I run Amsoil OE 5/30 and Toyota OEM filters.

Who knows, but it would be interesting to understand why as the oil has a little mileage on it that he oil pressure seems to drop at idle.

 

[BnvS]

Normal

Yup seems normal to me.

 

[JB Mitchell]

To follow up on, it does seem that once all of my LC 100’s once they have 2500 miles or so on an oil change the oil pressure at idle when the engine is warmed up seems to be very low at idle and in drive, but with a fresh oil change the pressure is definitely higher on the gauge at idle and engine warmed up. Both of my 100s have approx 250k miles that do not eat oil and have good power.

I run Amsoil OE 5/30 and Toyota OEM filters.

Who knows, but it would be interesting to understand why as the oil has a little mileage on it that he oil pressure seems to drop at idle.

I notice that as well. I find it hard to believe that the viscosity of the oil begins to break down that soon, but it seems to be a logical explanation. I have decided to run a little heavier oil to bump up my oil pressure. I use 5w30 and it has kept pressure very well from oil change to oil change.