High oil pressure?

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doug355r

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I searched this forum and a few others and didn't find an answer...could be too many beers lol

1996 K1500 with 99K miles.

I was on a trip up north of Phoenix this weekend and on the way up the mountain hills my oil filter blew off my truck(that's what I get for taking it to a shop for the change instead of doing it myself, only every paid for 2 on this truck. ) I was watching the pressure and temp gauge and everything was fine until then. I got it shut down super quick and towed to the closest city 30 miles away. Slapped on a new filter and re-filled the engine with oil and made it up to the campsite just fine, another hour or so of driving. Coming back today my idle pressure measured at 40 on the gauge and 60 under load in the highway, jumped to 65 when downshifting up some big hills. Can't tell if this is abnormal high pressure or not? Any help would be appreciated.
 

Texcuda

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iirc, your truck should have around 15 psi at idle and then go up as rpm's go up. It may be a stuck pressure relief valve in the pump. That would also explain the filter blowing off. My son had a 98 and the oil pressure always drove me crazy being soooo low. Good luck on tracking it down.
 

magimerlin

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Rule of thumb on chevy.... 10lbs per 1k rpms...

sent from what use to be a great country...
 

sntrym

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You are well within spec. My stock 350 with 316k on still runs at 30-40psi in idle when cold, 25 or so when warm, and 60-65 on the highway. Like magimerlin said, 10psi per 1k rpm, and that's minimum. High viscosity oils can increase oil pressure as well, so make sure you are putting the right stuff in, typically 5w30.
 

michael hurd

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Pressure is not an indication of flow. You can have high oil pressure and low flow.

If small orifices are plugged with carbon, you can have artificially high pressures.
 

Texcuda

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Rule of thumb on chevy.... 10lbs per 1k rpms...

sent from what use to be a great country...

with a standard pump sbc, definitely, but the vortec motors used a different spring to lower pressure at idle to lower parasitic loss. I didn't believe it either, so I checked my chilton and sure as sh*t, it was in there.

Edit: just checked the manual, 98 5.7 CSFI vin R = 18 psi @ 2000 rpm
 

Jrgunn5150

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I guess, all other considerations aside, the important thing is, did it change?

Did you have some other oil pressure and now it's higher?
 

doug355r

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Pressure was pretty much the same before the incident +/- 5 maybe.
 

Jrgunn5150

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I wouldn't worry over it then. I look for changes more than anything. If it didn't explode before, it probably won't now.
 
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