Hi oil psi

[steveRS2]

First time 5.0 owner here. Have 2017 Roush stage 2 mustang I just bought with 25k miles. Is it normal for the oil psi to go up to 90 psi at normal operating temp @ less than 3k rpm???

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[Nickel]

Have you checked the oil to make sure it's not overfilled? Are you changing the oil yourself?

 

[steveRS2]

Have you checked the oil to make sure it's not overfilled? Are you changing the oil yourself?

Oil level is at spec. I've only owned car a week so I haven't done anything to it

 

[Nickel]

Cold temps create higher oil pressure depending on where you're at. What does it sit at whenever you're idling?

 

[steveRS2]

I'm in SF bay area, was 75deg outside today. Fired it up and immediately noticed oil psi at 90...sat till car got to normal coolant temp, drove 10 minutes still 80 to 90 psi....

 

[CS19]

I'm in SF bay area, was 75deg outside today. Fired it up and immediately noticed oil psi at 90...sat till car got to normal coolant temp, drove 10 minutes still 80 to 90 psi....

What weight oil?

 

[steveRS2]

What weight oil?

No idea just bought the car a week ago....will change oil and filter tomorrow with manufacturer recommend oil

 

[Cobra Jet]

Yes, seeing that high of an oil psi upon “cold” startup and within 10-20mins of driving is completely normal - even if outside temps are 75*. Your cold start internal engine temp is not 75* just because it’s 75* outside of it.

Best analogy:
Take syrup or honey from a cold fridge - it’s very thick, sometimes hard to squeeze out of the bottle depending on brand. Let that bottle sit at room temp or heat that syrup or honey up and it flows much more fluid, because it has thinned out due to the warmer temps.

Cold oil, even if it’s 5w30 or 5w20, it still “thick” which creates higher oil psi; once it gets flowing (thins out) and engine temps are normal, oil psi at idle will be about 5-10psi less.

You will also notice even after the engine had warmed up to 190* +/-, depending on what gear your driving in, or downshifting into, the oil psi will jump higher... For instance if your driving around town in 4th gear doing 55mph, your oil psi will be higher than if driving around @ 55mph and lugging it in 6th gear.

 

[steveRS2]

Yes, seeing that high of an oil psi upon “cold” startup and within 10-20mins of driving is completely normal - even if outside temps are 75*. Your cold start internal engine temp is not 75* just because it’s 75* outside of it.

Best analogy:
Take syrup or honey from a cold fridge - it’s very thick, sometimes hard to squeeze out of the bottle depending on brand. Let that bottle sit at room temp or heat that syrup or honey up and it flows much more fluid, because it has thinned out due to the warmer temps.

Cold oil, even if it’s 5w30 or 5w20, it still “thick” which creates higher oil psi; once it gets flowing (thins out) and engine temps are normal, oil psi at idle will be about 5-10psi less.

You will also notice even after the engine had warmed up to 190* +/-, depending on what gear your driving in, or downshifting into, the oil psi will jump higher... For instance if your driving around town in 4th gear doing 55mph, your oil psi will be higher than if driving around @ 55mph and lugging it in 6th gear.

Thank you! I was kinda freaking out..... This is my first 5.0 ,I lack knowledge on this engine.

 

[steveRS2]

Still going to change oil and filter so I know 100% what's in crankcase.....

 

[GregO]

Still going to change oil and filter so I know 100% what's in crankcase

That’s a smart move. The idle oil pressure shouldn’t be that high after normal operating temperature is reached.
I use 0W-20 and Cold start up oil pressure hits 90 to 100 psi depending on outside temps.
Once normal operating temp is reached the pressure is somewhere around 40ish psi at idle and lower Rpm’s.

 

[gadgtfreek]

Mine never seems to get over 40 or so even when the engine is cold (70 degrees outside), but I've only had it a few weeks and might need to pay it more attention. The last service was done by a dealer. I'd agree with changing the oil.

 

[GregO]

Mine never seems to get over 40 or so even when the engine is cold (70 degrees outside),

Gen 3 Coyotes have a oil pump bypass that lowers the cold start up oil pressure. Prior Coyotes don’t have the bypass feature.

 

[gadgtfreek]

Gen 3 Coyotes have a oil pump bypass that lowers the cold start up oil pressure. Prior Coyotes don’t have the bypass feature.

Ah, explains that then, thanks.

 

[Elp_jc]

Yep. My 2019 Bullitt goes to around 90 psi upon start-up (M1 0W-30 here), and after a second or two, it drops to around 40. When hot, it's around 25, which is kind of low IMO, but I'm sure it's enough to lubricate the engine at idle properly (around 625 rpm).

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