oil pressure, how low too low

[dougimes]

I took the m715 on a shake down run of 60 miles or so getting ready for my leg of the Cross Country Convoy.

The only issue I see, after the truck is all warmed up and has been running a while, oil pressure stabilizes while at speed, I show about 10 to 15 PSI of oil pressure. At idle its less.


I am running 30 weight oil, straight grade. I am going to hook up a mechanical gauge tomorrow to verify the reading.

how low is too low?

 

[bcowanwheels]

make sure the oil line to the rear of cylinder head is good and not leaking reason being its where the oil pressure gauge sender is also located. these oil lines are notorious for going bad and costing you a engine. if its the stock oil line I,d change it out to steel tube line. this line is the only oil that feeds the top of the engine.

 

[frank8003]

25psig at 2000 RPM specification

bcowanwheels sent a good caution note
SOHC with cam lobes doing double duty with OE-30 oil. Put a good gauge on it, get the readings, put better oil in it, change the filter and measure it again. Can't hurt.

3-8. Oil. Pressure Check (In Vehicle).a. The oil pressure may be tested by installing a pressure gage at the oil passage fitting at right rear of cylinder block. This fitting connects block-to-head oil pipe, to cylinder block.b. Check oil pressure with engine at operating temperature (160°). Minimum pressure should be 10 psi at 600 engine rpm; 25 psi at 2,000 engine rpm.
View attachment TM 9-2320-244-34_M715.pdf

 

[frank8003]

M715 SOHC with cam lobes doing double duty with OE-30 oil.

The M715 LO denotes OE30 (MIL-L-45199) which was API service CD?
What I posted about put better oil in it is from a bit of an ongoing study of mine.
This is only a suggestion.
You can just put Rotella T (or your favorite flavor) in it and meet MIL-L-2104D, and later specifications
and get all the latest engine protections.
View attachment lubrication in practice M715.pdf

 

[bcowanwheels]

also seeings your in sc I,d run 50 weight Valvoline racing oil, it still has all the additives the 230 calls for mainly zinc. I run it all the time except dead winter then I run 2 qts and the rest rotella 15-40

 

[kvflyer]

My truck is in Florida and I run Rotella 15W40 all year. The oil pressure starts out at 55-60 pounds and does not drop below 30 pounds at idle. The engine has 14,000 miles on it.