Oil pressure drop after addition of OEM Oil Cooler?

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if that's they truck link, the valve there. arrow pointing to it.
I never knew that was a valve. I know it's not adjustable and that there is an o-ring under it that can start leaking and need replacing. I just thought it was a blocked off port for some unknown application, lol

Most people on here don't know what that port is for either, it's been discussed in other threads. Glad you shared this knowledge with us, and now we know
 
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Just Fishing

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On my tahoe, it's sensitive to oil level.
If i fill it to the F line on the dip stick, i get lower oil pressure.

I read it's something about the oil being foamed up by the crank.

If i keep the level just under the middle between full and add, it's much better overall.

But it might just be something with the replacement dipstick or the 2019 dated block i have.
 

strutaeng

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I rebuilt the engine on my suburban's LQ4 a few months ago and haven't reinstalled the oil cooler lines. It had them originally.

I was going to buy the Dorman, which has something they call "improved design" or something, but decided to simply go back with the GM Genuine. My old ones had started to deep a tiny bit. But I haven't installed it yet.

In theory yes, there should be a bit lower pressure because the oil has make it's way through the cooler and there's more friction. But 10 psi seems a little too much. IDK.
 

Charlie207

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Will do on the screen - next on the list. I remember on my '09 Tahoe, the PF63 actually improved oil pressure. And that one had the oil cooler from factory. I like the PF63 since it has more capacity. But I have a PF48E laying around that I could install just to see if it helps? Or do you recommend a different brand? I know some on here prefer Wix. Yeah, adding the cooler and lines (and taller filter) I'm at 6.5-7 quarts for the first oil change. I'm sure next one will be less.

I used a Dorman set for the lines. I'm not sure why I didn't go with the GM ones, wish I would have now. But the Dorman does have that same valve. Should I try and adjust?
2014 and older do not have adjustable valves. Those are in the 2015 and up, so you have nothing to adjust, or worry about.
 
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The MotorTrend show Engine Masters did an episode testing the amount of engine oil in the pan with an engine on the dyno. S3 E3 How Oil Kills Power.

Basically seeing the effects of more or less oil has on hp and oil pressure across the entire rpm range. A pan filled with the oil at the recommended level lost oil pressure at high rpms due to the airation and frothing of the oil by the crankshaft whipping it up. While the same test with 1 less quart of oil kept pressure and made more hp. Granted, this was above 5k rpms and most engines in daily driven vehicles won't be in that rpm range much to cause problems.

On that note, I've never added more then 6qts of oil when doing an oil/filter change, and I have the oil cooler.
 

j91z28d1

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I never knew that was a valve. I know it's not adjustable and that there is an o-ring under it that can start leaking and need replacing. I just thought it was a blocked off port for some unknown application, lol

Most people on here don't know what that port is for either, it's been discussed in other threads. Glad you shared this knowledge with us, and now we know


ahh I hadn't see the threads.

I believe this is valve under itself and can be replaced.


to the op. what radiator did you go with? maybe it's end tank is a bit restrictive? I don't know, just made me think when I was researching dwitts radiators they talked about the number of plates in there for more or less cooling. if you had a auto parts store one maybe it's just a tranny cooler on both ends with bigger fittings?

just thoughts.
 

j91z28d1

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The MotorTrend show Engine Masters did an episode testing the amount of engine oil in the pan with an engine on the dyno. S3 E3 How Oil Kills Power.

Basically seeing the effects of more or less oil has on hp and oil pressure across the entire rpm range. A pan filled with the oil at the recommended level lost oil pressure at high rpms due to the airation and frothing of the oil by the crankshaft whipping it up. While the same test with 1 less quart of oil kept pressure and made more hp. Granted, this was above 5k rpms and most engines in daily driven vehicles won't be in that rpm range much to cause problems.

On that note, I've never added more then 6qts of oil when doing an oil/filter change, and I have the oil cooler.


not that's it's relvent here, but as an odd thing. c6 corvette owners manual calls for adding an extra qt of oil over the full on the dipstick amount if it's going to be driven hard. I didn't believe it till I downloaded the owners manual and read it myself. very weird huh. I've done it, and then said eh and drove it a 1000 miles home without removing or. didn't see any oil pressure issues on the way, but then again looking back, it probably burned half a qt at the track lol. back before I know horrible the pvc system is at drinking tons of oil at high vacuum.

theory goes guys would take their stock cars to what corvette guys call "high performance driving academy" or something lame like that because they believe insurance will cover their car if they crash it because it's not racing if it's untimed, it just teaching. lol. but it's a track day and they got low oil pressure warnings and blown up motors under warranty. so gm has a delay in how long it can see 0 oil pressure before dash lights come on, it's even defined in hptuners so you adjust the time. that and add a extra qt of oil was their fix for the base cars.

built a half dry sump setup for the zo6's, which still rod knock of driven hard enough on long left hand sweepers, but it's not talked about outside if track guys because negative things would hurt the valve.

ls oil systems are kinda a mess for something that seems so simple.
 
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Weird, the listed vehicles this valve fits is 80s-mid 90s trucks/suvs and 2006-2014 vettes.

I wonder what's different on ~2000+ trucks/SUVs that this isn't used.
 
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not that's it's relvent here, but as an odd thing. c6 corvette owners manual calls for adding an extra qt of oil over the full on the dipstick amount if it's going to be driven hard. I didn't believe it till I downloaded the owners manual and read it myself. very weird huh. I've done it, and then said eh and drove it a 1000 miles home without removing or. didn't see any oil pressure issues on the way, but then again looking back, it probably burned half a qt at the track lol. back before I know horrible the pvc system is at drinking tons of oil at high vacuum.

theory goes guys would take their stock cars to what corvette guys call "high performance driving academy" or something lame like that because they believe insurance will cover their car if they crash it because it's not racing if it's untimed, it just teaching. lol. but it's a track day and they got low oil pressure warnings and blown up motors under warranty. so gm has a delay in how long it can see 0 oil pressure before dash lights come on, it's even defined in hptuners so you adjust the time. that and add a extra qt of oil was their fix for the base cars.

built a half dry sump setup for the zo6's, which still rod knock of driven hard enough on long left hand sweepers, but it's not talked about outside if track guys because negative things would hurt the valve.

ls oil systems are kinda a mess for something that seems so simple.
Many specialized aftermarket pans made for road racing or drag racing have baffles located at different places (depending if you corner or are going straight with a lot of Gs) to help keep oil around the oil pickup tube in these situations. Kind of like how a fuel tank has a reservoir area around the basket or fuel pump sock to keep fuel in that area.
 

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