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Oil Pressure dropping????

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Old Aug 9, 2013 | 11:24 AM
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Default Oil Pressure dropping????

So I live in texas and summers are constantly above 100 degrees. I drive about 50% city other 50% highway. After about 15-20 min of driving I notice my oil pressure drops to 35psi at a light, it usually sits right at 40 psi at a light. I notice the valve train gets louder also. I have checked time after time and no oil is being burned.

I use castrol 10W 30 would 10W 40 help this issue? I change my oil and filter every 2500-3000 miles
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Old Aug 9, 2013 | 11:35 AM
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35psi is plenty pressure at idle. don't sweat it.
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Old Aug 9, 2013 | 01:27 PM
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I agree with above. I would be more concerned if the pressure didn't go up with an increase in RPM. Does it still run the same pressure it used to at cruising speeds?
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Old Aug 9, 2013 | 02:07 PM
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I have switched over to Mobile1 in my new motor and I have noticed better oil pressure at idle with it.
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Old Aug 9, 2013 | 02:15 PM
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the oil pressure will go up with rpms but after 20min on the highway it drops 5 psi as well. Can hear the valve train in detail b/c the free way to work has concret guard walls and it gets noticable louder in the cab and off the wall when oil pressure drops 5ish psi.

70mph
0-20min 50psi
20min + 40-45psi

I was thinking maybe the hot 105-110 degrees is making the oil viscosity less thick after motor gets to operating temp and driven in the hot temp for 10-20min

Factory recommends using 5W 30 but I know this is b/c of northern climate truck sails. As my 10W 30 gets closer to changing time the valve train gets louder as well. I have been checking the oil every day or other day for the past month/1000 miles no burning
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Old Aug 9, 2013 | 03:36 PM
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Like said, don't worry about it. It is because the oil is getting hot and thinning out.
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Old Aug 10, 2013 | 12:48 PM
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Nice! Thanks guys for calming my paranoia haha
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Old Aug 10, 2013 | 02:14 PM
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I had a similar issue. Except mine would drop to 18-20 at idle when hot. When i dropped the oil pan my oil pickup screen was covered in crap. I cleaned it all off and swapped out pumps for a melling HV one. I have plenty of pressure now. I am betting most of my issue was the crap on the screen.
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Old Aug 11, 2013 | 10:19 AM
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Mine does this too. I wouldnt sweat it. I would cut the filter at your next oil change though to see if there is bearing material. I think the stock pump doesnt pump enough oil to enable the relief spring for the pressure. The pressure is then determined by the oil weight, and the bearing clearances.
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Old Aug 13, 2013 | 02:42 PM
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I cut the oil filter open and looked through the oil with a magnet yesterday, and no metal particles.

I switched to castrol 10W 40 synthetic. Oil pressure is now around 45 psi at idle, after a full hour of driving still around 40-45psi and no more valve train noise.

Lets see if it last for 3000 miles
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