All Oil Ain't the Same

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All purchased from AAP. 6 different stores in 3 counties


like I said, I ain’t bashing any oil. I probably should not have mentioned the brand. If I had a do over, I wouldn’t. My mistake. I don’t hate RGT.

just trying to point out that some oils may work better for your cars than others. That’s all.
I am questioning if it is a good idea to change brands. I can’t prove anything but I am thinking it’s best to pick an oil and stick with it.

Gebo, Let's rescue this thread from the silliness of the forum crowd.

If it wasn't the oil, maybe it was a fueling issue. Do you get the gasoline on both cars form the same vendor?

I've seen this mahogany/ red colour in my sump in the past when I got a bad batch of gasoline in engine that didn't deal well with mis-blended or "phase separated" gasoline: Gas with well over 10% Ethanol.
If your Station Dispenser doesn't have an inline SAP filter you wont know until its too late.

Can you read you ST/LT fuel trims for clues?
 
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If I could find them for a couple of my applications, I'm almost tempted to switch to centrifugal pumps JUST to open up a new thread about thick vs thin, MOFT vs flow 🙃
Then we could also talk about blown-up engines due to lack of lubrication in cold weather start-ups. :D
 
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Here you go with that again.
If you have bypass/regulator around the pump you DO NOT have an effective positive displacement OIL FLOW.
Where did I say a PD oil pump is always in pressure relief? PD oil pumps hardly ever go into pressure relief unless you're starting an engine with cold oil and revving it like crazy. Any time a PD is not in pressure relief, all oil leaving the pump goes through the engine ... anyone that knows how a PD pump in an engine oiling system should know that.

So if oil was not flowing you would have static head of say 60-70 PSIg and the volume of oil would flow around the pump

If it wasn't for bypass we would be blowing filter cans open and base gaskets off cars in cold weather.

-Ken
When the pump is in pressure relief, there is still lots of oil flow going to the engine. Oil doesn't stop flowing ... you know that right?
 

4WD

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^^^ Yep ... "When the PD oil pump is in pressure relief, there is still lots of oil flow going to the engine. Oil doesn't stop flowing".
 
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No, 2.4 vs 2.7 vs 3.0 doesn't make any difference to a PD oil pump.

Yes it does still flow the oil ... a PD oil pump ensures that happens, it forces oil volume and if it takes more pressure then that's what happens, the output pressure of the PD will just increase enough to put the same volume through the oiling system. That is the main reason that PD pumps are used in engine oiling systems.

The PD oil pump ... so misunderstood. :cry:
My simple research on these PD pumps says this pump is known as a constant flow machine -- that the volume of the fluid being displaced remains constant throughout its operating range -- regardless of the discharge pressure.

I suppose they could be and likely are designed to provide engines a minimum flow rate, adjusting flow rates upwards as needs arise. I suppose increased RPMs could drive that, along with engine loading.

Thank God for that!
 
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My simple research on these PD pumps says this pump is known as a constant flow machine -- that the volume of the fluid being displaced remains constant throughout its operating range -- regardless of the discharge pressure.
To be a bit more accurate in the wording, a PD pump is a constant volume output per revolution. The flow isn't "constant" unless you're saying at a fixed RPM. Of course PD pump output increases with the engine RPM up until the pump pressure relief valve starts to open. Plus, there is a certain degree of
"pump slip" (aka, pumping efficiency). PD pumps are also a bit more efficient (have a bit less slippage) with thicker oil. And of course as a pump wears out more and more the slippage increases - ie, it can't put out the same volume per RPM due to efficiency loss.

I suppose they could be and likely are designed to provide engines a minimum flow rate, adjusting flow rates upwards as needs arise. I suppose increased RPMs could drive that, along with engine loading.

Thank God for that!
The old fashioned PD pumps just put out more and more flow as the engine RPM increases, and starts cutting volume to the engine from slippage at higher RPM and as the pressure relief starts opening more and more. The newer computer controlled variable oil pumps change the pump flow based on running conditions ... all that complexity just to save 0.001 MPG.
 
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Never seen Rotella Gas Truck in a gallon jug. Only 5 qt and 1 qt containers.

Yours is the first negative I have seen about it.
I have only used ~9 qts of my stash, and no problems with it so far (4000 miles on the Scion xB and just a few hundred on the Kia Soul).
Same--have not heard anything negative about it. We (Jeep gang over on the Wrangler forums) went around and cleaned out AAP in our various locations when they clearanced it a while back. I have only done two 5K OCIs at this point, but so far so good.
 
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To be a bit more accurate in the wording, a PD pump is a constant volume output per revolution. The flow isn't "constant" unless you're saying at a fixed RPM. Of course PD pump output increases with the engine RPM up until the pump pressure relief valve starts to open. Plus, there is a certain degree of
"pump slip" (aka, pumping efficiency). PD pumps are also a bit more efficient (have a bit less slippage) with thicker oil. And of course as a pump wears out more and more the slippage increases - ie, it can't put out the same volume per RPM due to efficiency loss.


The old fashioned PD pumps just put out more and more flow as the engine RPM increases, and starts cutting volume to the engine from slippage at higher RPM and as the pressure relief starts opening more and more. The newer computer controlled variable oil pumps change the pump flow based on running conditions ... all that complexity just to save 0.001 MPG.
Correct... I did read about that consistency through the revolution cycle. And I suppose the "minimum" flow will come from an engine's idle.

Thanks for the clarification!

All of this reminds me of my occasional visits to certain Alyeska Pipeline (the Trans-Alaska Pipeline Operating Company) Pump Station pump rooms while the engineering technicians were accomplishing maintenance as a walked by. I suspect they were PD pumps as well. Back then, the pump(s) were spun by quite large and noisy turbine engines! Hearing protection was most definitely required! Nowadays, they are spun by electric motors. That's progress for you...
 
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Where did I say a PD oil pump is always in pressure relief? PD oil pumps hardly ever go into pressure relief unless you're starting an engine with cold oil and revving it like crazy. Any time a PD is not in pressure relief, all oil leaving the pump goes through the engine ... anyone that knows how a PD pump in an engine oiling system should know that.


When the pump is in pressure relief, there is still lots of oil flow going to the engine. Oil doesn't stop flowing ... you know that right?
I build performance engines in my leisure time for friends. Not five a week, but maybe 5 a decade.

In my statement, It was obvious - to me at least :) - that a PD pump with a pressure relief you hit a "static" head value, where spinning the pump faster no longer results in a linear increase in volume output.

It's like pushing with a spring rather than forcing with a ram rod. Once you have a functional bypass system around the pump it does NOT act as a positive displacement pump as a "system"

When these pressure limiting bypass systems get stuck and the pump IS operating as a PD, you WILL blow filters off engines and blow out seals. Seen it happen.
 
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RGT just might be the best oil I’ve used. I used it in my Silverado, it cut my oil consumption down. Used it in my Avalon...did what every other does in my Avalon...not use a drop, quiet, doesn’t turn dark and then I drain it after 5,000 miles.

There have been multiple “test” videos on it on YouTube...UOA after 14,000 miles, tested great with great returns from the analysis. Project Farm had a competition/playoff with 16 different major brands competing against each other...I think it finished 4th or 3rd, with Amsoil winning.

Aside from having the ugliest bottle in the business, I like like it. Having said that, I only buy whatever I can get on rebate or sale...right now that’s Pennzoil platinum...which I believe is made by the same company that makes RGT. And I’m currently working down my stash...just changed my oil yesterday using Quaker State Ultimate Durability (which I believe also is made by the same manufacturer as RGT).
PF didn't include RGT in his oil competition. You're thinking of Pennzoil Ultra Platinum.

Yes, Pennzoil, Quaker State, and Rotella are all SOPUS products.
 
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Yeah depending on what you use in those Camry what I have found is they are very sensitive especially the new ones because the oil ports are so small. Which is why a W-20 is recommended. So if you weren’t using a W-20 I could see why it used a lot. Depending on the year and engine some of them had consumption issues.
And then there is my hero @xgmad with his heavy oil fetish in modern cars. It definitely keeps the timing chains happy, and I bet HDEO is cheaper per oil change than PCMO, especially trying to find PCMO that meets all VW certs. This man must be doing something right, huh?

Volkswagen jetta 2011 2.5 has over 300,000 miles - 15W40.
Camry 2013 has over 176 thousand - unknown, probably a 15W40 as well.
2020 camry has 35,000 - 20w50.
2014 VW Jetta 2.0L has 112,000 miles - 15w40.

Eventually we all come to a conclusion that oil is oil and there are more important things to worry about in life than oil...
 
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And then there is my hero @xgmad with his heavy oil fetish in modern cars. It definitely keeps the timing chains happy, and I bet HDEO is cheaper per oil change than PCMO, especially trying to find PCMO that meets all VW certs. This man must be doing something right, huh?

Volkswagen jetta 2011 2.5 has over 300,000 miles - 15W40.
Camry 2013 has over 176 thousand - unknown, probably a 15W40 as well.
2020 camry has 35,000 - 20w50.
2014 VW Jetta 2.0L has 112,000 miles - 15w40.

Eventually we all come to a conclusion that oil is oil and there are more important things to worry about in life than oil...
Haha, heavy oil fetish!!! I use them because I think that HDEO's are cheaper and alot more better for reliability than marginal fuel economy. HDEO's do SHEAR, but they shear less.

My parents honda odyssey 2006 has been using 5w20 all its life...yeah it lost some compression while my thick oil cars haven't. There is more lifter noise, I can hear some weird scraping, but theres no oil burning because It's not been abused, the rpm's do not go above 3,000.

Why waste money for a 5w-x when i can use 15w40 and change it every 7,8, or 10,000 miles? I've stretched synthetic blend castrol GTX 15w40 for 14,000 miles a couple times because my dad forgets to change it, and sometimes I get too lazy to even think about it, still is good when I change it (all of my thick oil engines gets sustained rpm's above 4,000).

HDEOS have a decent additive package, phosphorus, zinc, and calcium, and a little bit of boron, not much else you really need.

All those certs are bs when it comes to using hdeo's, it shall surpass! haha!

All Volkswagen group cars should follow this 502.00 chart. You should probably use it for any other engine too! I like this chart, its what I go by.
VW has been turboing their cars for a long time, alot of it hasn't change but slight modifications. The 2.0's and 2.5's? Yeah not much difference, some audi's have highly tuned 2.5's but you should still go by this chart.
502.00.jpg
 

4WD

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Nice chart. Obviously a turbo engine.
I knew those piston jets would be hungry buggers but not that hungry.
I might consider to build a looser rod (and main )journal and let that give the underside the oil.
wonder if having PJ’s are not a reason my 2017 5.3L on 0w20 is quieter than my 2010 5.3L was on 5w40 ?
 
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And I wonder if having PJs are a reason my heaps are quieter with 15w40 as opposed to 10w30/5w40.

Oh wait - must be because I replace the plastic PJs with billet nozzles, polar attracted ionic flow & all that.

And yes, very slightly looser toleranced mains & rods along with an HV gerotor pump as well ;-)
 
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In my statement, It was obvious - to me at least :) - that a PD pump with a pressure relief you hit a "static" head value, where spinning the pump faster no longer results in a linear increase in volume output.

It's like pushing with a spring rather than forcing with a ram rod. Once you have a functional bypass system around the pump it does NOT act as a positive displacement pump as a "system".
In post #57 you said:
"If you have bypass/regulator around the pump you DO NOT have an effective positive displacement OIL FLOW. So if oil was not flowing you would have static head of say 60-70 PSI and the volume of oil would flow around the pump."

That is a confusing way to describe a PD oil pump IMO - you say "so if oil was not flowing". Even if the pump is in pressure relief there is still oil flowing - plenty of oil as shown in the graph in post #64. Oil is never not flowing. You make it sound like all flow stops. Your statements however in post #72 makes more sense.

When these pressure limiting bypass systems get stuck and the pump IS operating as a PD, you WILL blow filters off engines and blow out seals. Seen it happen.
Yes, the PD pump is operating as a PD any time it's not in pressure relief. I've been saying that all along - only wrinkle is pump slippage/efficiency going on when the pump is not in pressure relief. That just means it's not a perfect linear volume output vs RPM, and the design and health of the pump has a bearing on its pumping efficiency curve before pressure relief happens. And yes, if the pump didn't have a pressure relief valve it would over pressurize the whole oiling system ... could possibly also blow out oil seals in the engine.
 
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