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

[j91z28d1]

Mine at 130k miles w/good oil pressure. Broke when I pulled it off.
View attachment 397081

I have see that a lot over the years, a o ring that's fine, till you pull it off and try to take it off. it then splits. not on these trucks, just general stuff I work on.

I wonder if gm only putting the one bolt on let's the tube move around enough for the o rings to break while still inside their groove

 

[j91z28d1]

by higher oil pressure this is what I mean, what gm calls out as acceptable. I'm still not sure what you actually see in the gauges?


*see attached*
so basically it says 22psi at 1000rpm and doesn't set a engine light till 15 ish. I'm guessing by a 600rpm idle that would be 10ish?


the spec for the 08-13 6.0 hybrid with the variable displacement pump calls for a different spec.
oil pressure spec hot
36psi @1000
42psi @2000
45psi @4000
afm relief valve 55-75 max.
p0521 ecm detects different oil pressure than expected by lower 6.8psi or greater than 7.3 psi for 10sec

seems like a big difference in pressures for basically the same engine. that's all I meant by that comment. it doesn't really idle when it's hot, it auto stops, I'd have to see force it to run and see what it idles at. but any time it comes out of auto stop it goes straight to the mark between 40 and 80. you've got me curious. I'll have to check. I've never noticed it below 40psi. I've got a legitimate dealer bought new sender on it. I agree there seem to be some counterfeit ACDELCO parts on Amazon. they got me the 1st time.

I'm still wondering what a standard 5.3 idles at when hot in a low mileage one?


my ls3 is in a c6. on 5w30 at 200deg temp it is around 38psi.(no afm or vvt) but that's a manual idling at either 750 or 800rpm. I can't remember now, bumped it up a few rpm at idle for the alternator voltage after I put a underdrive balancer on it. so not really applicable, I only mentioned it because it's over 100k and I've had it above 300deg oil Temps a few times at the track and mountains before I got the Temps under control and just changed the o ring out cause I was in there. it was the original one, blue color for the sizing but it was perfect. couldn't tell a difference between it and the new one I got from the dealer to replace it.

 

[j91z28d1]

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.

do you happen to remember the how much different it made on the one that it improved?

 

[j91z28d1]

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?

I agree that normally running higher oil pressure than needed, like a high volume high pressure pump on a stock engine will waste hp. in fact millings recommens not increasing either one unless there's a need over stock levels.

funny thing is, everything I read says the veritable displacement pump saves 1.5hp but seem the spec is higher pressure. I didn't think about the aluminum block to iron, they do grow more when hot. not sure if they run a smaller starting main bearing clearance compared to the iron.

only because I just looked it up inspecting my other one, the aluminum ls3 min mains are 0.0008 and even my every so slightly worn ones where at 0.001.(not that I can measure that small of an amount consistently with my tools, but I tried lol.) which would be super tight for a iron block.

wonder if they left the mains loose on this aluminum 6.0 and just over volumed the pump. I'll have to look at the min and max spec later and compare to a iron 5.3

 

[swathdiver]

I agree that normally running higher oil pressure than needed, like a high volume high pressure pump on a stock engine will waste hp. in fact millings recommens not increasing either one unless there's a need over stock levels.

funny thing is, everything I read says the veritable displacement pump saves 1.5hp but seem the spec is higher pressure. I didn't think about the aluminum block to iron, they do grow more when hot. not sure if they run a smaller starting main bearing clearance compared to the iron.

only because I just looked it up inspecting my other one, the aluminum ls3 min mains are 0.0008 and even my every so slightly worn ones where at 0.001.(not that I can measure that small of an amount consistently with my tools, but I tried lol.) which would be super tight for a iron block.

wonder if they left the mains loose on this aluminum 6.0 and just over volumed the pump. I'll have to look at the min and max spec later and compare to a iron 5.3

Do you have a Gen IV Hybrid 6.0 motor? Those and the newer LT engines have the variable displacement oil pumps. Yes, the aluminum blocks have more open tolerances once warmed up, that's why their pumps are spec'd to pump 1/3 more oil per revolution and run with a lower bypass spring, in the 30s. All my trucks run with oil pressure in the upper 30s while cruising down the highway.

An LC9s crankshaft main bearing clearance in production is .0008-.0021 and to .0025 in service. Definitely tough to see! Now with my old eyes it'll have to be "close enough for tv"!

 

[iamdub]

.I wonder if gm only putting the one bolt on let's the tube move around enough for the o rings to break while still inside their groove

I've seen the kits to add a bolt to the other side. But I'm just not buying that it's a problem if the tab on the tube or the tube itself isn't bent out of shape and correct hardware is used and torqued properly. The other end of the tube is bolted to one of the studs on the windage tray.

 

[j91z28d1]

yeah it's a 2011 hybrid. I've seen a tear down of the new LT oil pump and it's totally different. much larger and would not even fit these Gen 4. I've yet to see one of these in person. just the part number. seems millings has a listing as well as the oem gm. unless they made the pump for gm.

but it is said to fit in any ls block. I've seen them talked about on the corvette boards because of the hp savings.


upper 30s cruising at I'd guess under 2k? that seems like good oil pressure to me. do you happen to know what it idles at out of curiosity? at what point would you be concerned it was to low?

if I get time tomorrow, I'm going to hook up a scanned and force mine to not auto stop and see what it idles at warm.

not that has anything to do with my original post, but yeah. kind of an off topic oil pump post at this point anyways.

 

[j91z28d1]

I've seen the kits to add a bolt to the other side. But I'm just not buying that it's a problem if the tab on the tube or the tube itself isn't bent out of shape and correct hardware is used and torqued properly. The other end of the tube is bolted to one of the studs on the windage tray.

yeah, I forgot it was bolted to a main stud. I do remember listening to this a while back while mowing the yard, and one of the questions at the end Q&A was if the cheap little add one extra pipe hold down was worth doing, and if I remember right, they said yes for the cost, it's cheap insurance and might be some movement at high rpm vibrations.

 

[iamdub]

by higher oil pressure this is what I mean, what gm calls out as acceptable. I'm still not sure what you actually see in the gauges?

LOL @ what GM calls out as acceptable, especially on the subject of oil consumption.

*see attached*
so basically it says 22psi at 1000rpm and doesn't set a engine light till 15 ish. I'm guessing by a 600rpm idle that would be 10ish?

Thankfully, it's not so linear. Mine hot idles around 650 and 25-27 PSI. 1,000 RPM takes it to mid-30s. 2,000 RPM is good for around 42 PSI. My guess is that one, at hot idle, would be around 20 PSI.

the spec for the 08-13 6.0 hybrid with the variable displacement pump calls for a different spec.
oil pressure spec hot
36psi @1000
42psi @2000
45psi @4000
afm relief valve 55-75 max.
p0521 ecm detects different oil pressure than expected by lower 6.8psi or greater than 7.3 psi for 10sec

I didn't know you had a Hybrid nor did I know it had a variable displacement pump. I only knew of GenV engines having them. I also just realized my pressures are spot-on with the Hybrid specs. Mine's a 222K-mile LMG with a high volume pump (Melling M295HV, also ported),
plugged AFM towers and plugged AFM relief valve port.

seems like a big difference in pressures for basically the same engine. that's all I meant by that comment.

I see what you mean now. Yeah, those spec'd pressures do seem higher than the non-Hybrid engines. I think they allow low-20s at hot idle and under 40 cruising (1500-2000). Still plenty.

I'm still wondering what a standard 5.3 idles at when hot in a low mileage one?

I think they varied wildly from the factory. Mine, at 200K when it was still stock was around 3-5 PSI lower average across the board from where it is now.

 

[iamdub]

do you happen to remember the how much different it made on the one that it improved?

I don't remember. They might not have even specified. A lot of "non-established" members tend to vanish after getting the answers they seek and this might've been one. But, they were also one of the few that reported back. All I remember was that they said something about their pressures immediately improving so now they know their oil pressure issue was due to the O-ring.

The low pressure caused by a failed O-ring can vary in significance. It could be slight split that just allows a little air in and it could even be intermittent due to temperature. So the pressure starts out fine then drops or starts outs low then stabilizes. It could also be brittle and cracked at multiple points, causing a big leak, preventing the pump from priming.

The test is conclusive either way. By submerging that point in oil, the O-ring is taken out of the equation. It's not gonna make the pressure higher than it'd be if the O-ring was good. It just makes the pressure where it would be if the O-ring wasn't bad.