Low oil pressure and rough idle

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Isaac nickerson

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I am over 30 psi for highway speeds. It's mainly the idle that concerns me. But the highway seems to be a little lower that is has been prior.
 

bucket

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10-15 psi at idle is perfectly fine to be driving around, no need to be alarmed.
 

Isaac nickerson

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I topped off the oil today and raised the idle. Idling at 15 and cruising at 32. High revs I get up to 45+ and 50 at warmup. Although it is a little lower than it used too be. When I had the 8 psi the other night it was after 40 miles of driving at 65 mph, longer that most of my trips. So all that said it seems too slowly drop as it idles longer but I'm just gonna keep driving it and monitor it.
 

Isaac nickerson

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It's been behaving the same for the last few days. Decided that I'm going to change the oil to a thicker oil. Wondering whether I should run high mileage, sythenic, or just the normal stuff. Up till now I've been running o'Reilly's 10w 30 full synthetic.
 

bucket

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Still idling low and rough?
 

Isaac nickerson

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No were up to 800 rpm running fairly smooth. Just a tiny bit of sputtering out the exhaust but overall sounds good.
 

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I wouldn't go past 10w40. If the engine had some very worn bearings and the oil pressure was deathly low, then there could be some benefit to going with much heavier oil. But imho, there's no sense in trying to significantly raise the oil pressure, just for the sake of raising it. The last readings that you posted seem perfectly fine to me.
 

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