the add to quarts of oil test? has it worked for anyone?

[j91z28d1]

only really reading up on this Gen engines now and don't want to hijack another thread.
it makes sense and I see it recommended a lot, has anyone done it and it raised oil pressure? if so, how much?

I only ask out of curiosity. mine is an 11 with 145k has really high oil pressure, but being a different style oil pump it doesn't really count, the spec is much higher too and my other ls based engine I have now is a ls3. it's got 110k ish on it, I just had the pan off it to inspect bearings, for another reasons(blown oil line during a truck day) and changed out the o ring, it was a blue one. and it was super soft and it looked exactly like the new oem one I put in. I did have a 02 z28 years ago I put a ton of hard miles on and never changed oil till it said to, and used cheap bulk oil in whatever weight I had access to. (back in the broke kid days haha ran 87 in that poor thing all the time too haha) never noticed oil pressure change over the life of it.

just leaves me wondering what gm did with all these truck o rings that they fail so often. especially when the factory spec for oil pressure is called out to be so low that like 10psi hot idle is considered fine by it. how much of a drop is normal that leads guys to this board searching for reasons?

 

[OR VietVet]

If you have "high" oil pressure now and are experiencing no concerns, if the norm drops an uncomfortable level, that is when you start worrying. Then you search for the answer. Lot's of threads here about oil pressure concerns and sounds like you have been reading them. Whatever led the OP to post about an oil pressure concern, that is what you look for too.

 

[j91z28d1]

I'm just reading the threads cause it's interesting, I'm asking cause I have nothing to compare to. mine has a variable displacement pump, and much higher oil pressure than a normal truck. so mine doesn't tell me anything useful about others. just to be clear, my truck is fine. I'm not asking for me. it's more I've been a maintenance mechanic most of my life and have a general curiosity about it.

the threads I have seen pretty much have no info, I haven't seen any that said what their oil pressure was before and then what it dropped to now that caused their concern. usually the question is asked, but by then the thread is dying off and there's no reply. same with the add oil tests. I see it said to do it, but not seen anyone do it and report back that it helped.

this is all just random curiosity on my part. I'm not saying anything is wrong or not just see guys that have been on here a lot longer answering questions and wondering if they have seen a bunch of cases of the adding oil working? I caught a comment of a member ran his over filled a year or so before he could fix it and it left me wondering how often it works.

I haven't scrolled back to far in time, has there been many posts that ended up hurting bearings from low pressure or is it more the low pressure kills the afm lifters first?

 

[Dustin Jackson]

Here is a braindump of my observations.

GMT800 - Can have lifter failure, usually caused by lifters turning in the plastic tray, these lifters can eat the cam when turned and damaged. I see some threads on oil pressure concerns but like you said they usually have no conclusion, I suspect that is because these motors can survive on very little oil pressure and the motor keeps running (and the OP doesn't post because they stopped worrying) or they have money to spend and buy a new motor or rebuild it.

GMT900 - Introduces the AFM system and basically every point of the system has the potential to leak oil pressure or outright fail. Lifters now have more ways they can fail, VLOM malfunctions contributing to oil pressure loss and lifter failure. AFM system eats lifters and cams. You see alot of threads about low oil pressure concerns, some threads they are able to improve their oil pressure by replacing the o-ring or throwing their purse at it but 99.99% of the threads leave the user unsatisfied with what their oil pressure gauge reads. I suspect this has to do with the oil pressure sensors in circulation. When I did my AFM delete I replaced my oil pressure sensor while I had the motor open and my oil pressure gauge doesn't read the same as it used to and I think it is just the oil pressure sensor I used.

I think the oil pressure gauge these days is unreliable and is not fulfilling the purpose that users are relying on it to do. Also I have heard people say "every chevy I've owned has never dropped below 40PSI oil pressure so you engine is ******".

The only oil pressure gauge I can trust is my ear, I listed to the motor and if it doesn't sound like someone is stirring a silverware drawer I send it, I've done this for all my vehicles. I had 1 Dodge 5.9 with a dying motor due low oil pressure after someone rebuilt it wrong and it sounded terrible so I know what low oil pressure sounds like, I understand a lot of people haven't had that experience but they try to trust their cluster and it disappoints them.

 

[j91z28d1]

that makes sense. the afm does seem to be a good way to lose pressure.

I still not sure the "oem" Amazon sensor is correct. enough that I'm changing the 2nd one I got from them out soon most to see.

so what is the average pressure for say a good running 50k mile 5.3 with the afm vvt stuff warm on the 5w30? I know the gm spec is very low before they consider it a problem but what's real world when everything is still tight. also these things seem to idle in gear at like 600rpm. that's not much to ask for 40psi warm


I do also agree that ls engines, at least the bottom end doesn't need much oil pressure, if you ever follow sloppy mechanic, he does the grab a junk yard 5.3, stick it in a car with a big turbo, run e85 and don't replace anything type builds. he has gone 8s in the 1/4 with a 4.8 that idles at 10psi oil pressure. now no afm to keep alive, but that's a lot of load on the bottom end, if these engines needed a ton of oil pressure, he would kick a rod out by the 60 foot mark lol.


my ls 3 blew a oil line deep into a session, oil Temps above 250 at the time, and I didn't know it happened till I hit the brakes and went for a ride. looking back at the oil trail, it happened early in 2nd, so full wot pull in 2nd, shift to 3rd and full pull to almost redline, lift off throttle full engine braking and a down shift to 2nd as I hit the brakes and went for a spin. come to a stop, pull off the track and kill the engine. it was a main oil cooler line so none or very little oil went to the engine. I guess some would, but I'm guessing next to no pressure.

I figured bearings were toast at least if not cam. pulled the pan, check bearings and bearly even a scratch. I've seen new bearings look worse after checking with plastic gauge lol.

so yeah, I don't think atleast the bottom end of a low rpm daily driver needs a ton of pressure to survive. it does leave me wondering why the hybrid has such a different oil pump and pressure spec thou. it's basically the same thing. just starts a million times more over its life haha.

 

[Foggy]

1st of all: lots of fake/counterfeit parts out there... IDK if amazon is the best source...
and these gauges are just a guideline at best, esp the coolant temp...
2nd: the actual "TEST" that OP is asking about basically drowns the oil pump inlet
in oil and ONLY is an indication of the condition of the oil pump inlet tube pick-up O RING only.

The test is: add 2 quarts extra to an already warmed up engine. Park downhill (pretty decent
grade is needed for oil to slosh to front of pan)
Don't rev engine.. IF you see a significant increase in oil pressure on your gauge or scanner,
then you prob have at least a deteriorated O-RING (you may have other issues too)
But this test is only for the O Ring.
Then, don't drive around with the extra oil... Get it to the correct level immediately or you'll
be dealing with way more issues soon enough

 

[swathdiver]

just leaves me wondering what gm did with all these truck o rings that they fail so often.

This is not true. When the o-ring gets brittle is when they fail and then they good for another similar duration of about 165K miles.

What does "really high oil pressure" mean? Gen IV LS engines come in an aluminum and iron block variety. Each has a different pump and pressure bypass spring.

Increasing a healthy engine's pressure is usually a waste of horsepower and gas mileage unless one is racing it and even then my own experience was to leave a good thing alone.

Which engine is in your 2011? What kind of car is your LS3 in?

 

[iamdub]

mine has a variable displacement pump,

It does?

and much higher oil pressure than a normal truck.

What PSI? According to the gauge on the dash?

the threads I have seen pretty much have no info, I haven't seen any that said what their oil pressure was before and then what it dropped to now that caused their concern. usually the question is asked, but by then the thread is dying off and there's no reply. same with the add oil tests. I see it said to do it, but not seen anyone do it and report back that it helped.

I wanna say there has been at least two within the past year where they reported the results of the overfill and nosedive test. IIRC, one had an immediate rise in PSI and the other had no difference.

 

[iamdub]

just leaves me wondering what gm did with all these truck o rings that they fail so often.

They really don't fail so often. It's an age thing. The O-ring loses elasticity, shrinks, gets brittle and splits. It's in a rather harsh environment of chemicals and temperature swings. They commonly last well over 150K miles.

It IS a common failure in higher-mileage engines and that's when you see posts about testing it.

 

[donjetman]

Mine at 130k miles w/good oil pressure. Broke when I pulled it off.