Oil grade vs pressure vs volume

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Clevy

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Alright. So I've got a question.
So ford says 5w-20 is fine in a dohc 4.6. Apparently 10 pounds per 1000 rpms is the accepted oil pressure in a performance application. What if I put in a higher volume pump,could I in theory use thinner oil and still attain the desired 10 psi per 1000 rpms. Engine does have an oil cooler.
What is I used thicker oil? What possible outcomes could be expected.
Again. Hypothetical. Comments......
 
No, a higher capacity oil pump will not in any way change the viscosity requirements of an engine. It is not the oil pressure that provides protection at all. By relying on OP spec's, it's the back pressure or resistance to flow that an OP gauge measures that indirectly and secondarily can be used as a viscometer of sorts, but you must first know what the acceptable OP spec's are, and proceed from there.

The 10psi/1,000 rpm rule is a ballpark guide.
What you really want to get is the actual factory test OP spec's for your engine. You also will want to know the oil pump by-pass point.
Do you have an OP gauge currently installed?
With a gauge you will see what the OP characteristics are of your engine on the factory oil and you should always be confortably above the minimum OP spec's therefore it would not be necessary to start a heavier oil, in fact you very likely should be able to take advantage of the lighter 0W-20 oils such as the TGMO 0W-20 if you can maintain the spec' OP.

The problem of running a heavier than spec' oil is that to be effective you must be seeing higher oil temp's than normal oin a regular basis otherwise you could be running the engine in by-pass mode at high rev's with is counter-productive to the longevity of your engine.
 
Quote:
The problem of running a heavier than spec' oil is that to be effective you must be seeing higher oil temp's than normal oin a regular basis otherwise you could be running the engine in by-pass mode at high rev's with is counter-productive to the longevity of your engine.


I pose this question again.

Only 3 countries out of the 197 in the world spec XW20 routinely with the exception of some hybrids.
These are the same engines sold globally with the same clearances and internal specs. Many spec oils in the HTHS range of 3.5+ in the global market place.
.

So 194 of these countries are running their engines possibly in bypass and reducing the life of their engines?
I heard the argument of one poster that was "well our conditions are different" which is just not true either.

Point to any area of the US and there is a country with very similar conditions.
Your philosophy is basically claiming that these 3 countries are correct and the rest of the world is wrong is it not?

If its not then do you agree that heavier oils can and do protect the engine as well as a XW20 and provide the same engine longevity in the same engine?
 
I'm pretty sure this engine has an internal pressure by-pass. So obviously too much pressure is counter-productive. I guess what I'm asking is if flow is increased could thinner oil be used and not harm anything.
I'm not convinced of the whole thinner is better idea yet,so I'm kinda with trav on that issue.
I was thinking of buying a high volume oil pump however the stock ford piece is the highest volume pump ford makes and I would have to buy a melling. But going along the lines of caterham's viewpoint of going as thin as possible,while still maintaining proper pressure,but apparently I'm way over thinking the whole thing.
I'd still like to see the opinions though.
 
Originally Posted By: Clevy
I'm pretty sure this engine has an internal pressure by-pass. So obviously too much pressure is counter-productive. I guess what I'm asking is if flow is increased could thinner oil be used and not harm anything.
I'm not convinced of the whole thinner is better idea yet,so I'm kinda with trav on that issue.
I was thinking of buying a high volume oil pump however the stock ford piece is the highest volume pump ford makes and I would have to buy a melling. But going along the lines of caterham's viewpoint of going as thin as possible,while still maintaining proper pressure,but apparently I'm way over thinking the whole thing.
I'd still like to see the opinions though.


What do you hope to gain from using something higher volume than the factory Ford piece that already moves an absolutely obscene amount of oil?

The oiling system on the Modulars is not a weak point. You are over-thinking this.

If you want a bit more protection, I'd use something along the lines of Mobil 1 0w40, GC 0w30....etc.

Use an oil temp gauge and an oil pressure gauge to make sure you are playing safe.
 
I'm learning that oils with a high viscosity index are ideal at start up,but I do plan on tracking this car,and I love how 5000 rpms sound on these engines. So it's going to spend much of it's life playing the elevated exhaust note,like music for my ears.
Do European and Australian cars engines last any longer than our north American engines do? I wonder if there is a difference in longevity,which may quell the thick vs thin debate(maybe not though)
 
Originally Posted By: OVERK1LL
Originally Posted By: Clevy
I'm pretty sure this engine has an internal pressure by-pass. So obviously too much pressure is counter-productive. I guess what I'm asking is if flow is increased could thinner oil be used and not harm anything.
I'm not convinced of the whole thinner is better idea yet,so I'm kinda with trav on that issue.
I was thinking of buying a high volume oil pump however the stock ford piece is the highest volume pump ford makes and I would have to buy a melling. But going along the lines of caterham's viewpoint of going as thin as possible,while still maintaining proper pressure,but apparently I'm way over thinking the whole
thing.
I'd still like to see the opinions though.


What do you hope to gain from using something higher volume than the factory Ford piece that already moves an absolutely obscene amount of oil?

The oiling system on the Modulars is not a weak point. You are over-thinking this.

If you want a bit more protection, I'd use something along the lines of Mobil 1 0w40, GC 0w30....etc.

Use an oil temp gauge and an oil pressure gauge to make sure you are playing safe.


Your right. It was a thought. And I figured you guys here know way more about this than most in any mustang forum I'm in.
I already bought an oil temp gauge and a real oil pressure gauge. I'm waiting on the finding the perfect mount. I'm not sure if a pillar mount,or hood maybe.
Would a hood mount affect the temp reading even with a small shroud in front of them?
 
Originally Posted By: Clevy
I'm learning that oils with a high viscosity index are ideal at start up,but I do plan on tracking this car,and I love how 5000 rpms sound on these engines. So it's going to spend much of it's life playing the elevated exhaust note,like music for my ears.
Do European and Australian cars engines last any longer than our north American engines do? I wonder if there is a difference in longevity,which may quell the thick vs thin debate(maybe not though)


Well, food for thought, my M5 has a 400HP 5.0L DOHC V8, very similar to the Modular engine. Originally spec'd TWS 10w60, later models like mine with revised rings spec an LL-01 oil, which has a minimum HTHS of 3.5cP (the same as the two oils I already mentioned here).

Redline is 7,000RPM.

Peak power isn't made until 6,800RPM.

There are a number of high mileage examples of the S62 out there. Many, MANY more of the M62, which is the non high performance version of the engine, displacing 4.4L and making ~300HP. This was found in the X5, 540i, 740i...etc.

Oil like Mobil 1 0w40, GC...etc. are popular and often dealer fill for many of the high performance euro apps with high power density and that will see track and autobahn usage. I think this likely fits what you are hoping to observe driving-style wise in some manner, so I think their lubricant choice is particularly relevant here. JMO.
 
Originally Posted By: Clevy
Originally Posted By: OVERK1LL
Originally Posted By: Clevy
I'm pretty sure this engine has an internal pressure by-pass. So obviously too much pressure is counter-productive. I guess what I'm asking is if flow is increased could thinner oil be used and not harm anything.
I'm not convinced of the whole thinner is better idea yet,so I'm kinda with trav on that issue.
I was thinking of buying a high volume oil pump however the stock ford piece is the highest volume pump ford makes and I would have to buy a melling. But going along the lines of caterham's viewpoint of going as thin as possible,while still maintaining proper pressure,but apparently I'm way over thinking the whole
thing.
I'd still like to see the opinions though.


What do you hope to gain from using something higher volume than the factory Ford piece that already moves an absolutely obscene amount of oil?

The oiling system on the Modulars is not a weak point. You are over-thinking this.

If you want a bit more protection, I'd use something along the lines of Mobil 1 0w40, GC 0w30....etc.

Use an oil temp gauge and an oil pressure gauge to make sure you are playing safe.


Your right. It was a thought. And I figured you guys here know way more about this than most in any mustang forum I'm in.
I already bought an oil temp gauge and a real oil pressure gauge. I'm waiting on the finding the perfect mount. I'm not sure if a pillar mount,or hood maybe.
Would a hood mount affect the temp reading even with a small shroud in front of them?


The pillar or vent mounts are my favourite. They are the least intrusive, somebody isn't going to rip them off, and they aren't distracting but easy to see.
 
Originally Posted By: Clevy
Ya. Overkill. I almost hate to admit that Mobil's 0w-40 might be ideal for my particular application.
Darn.


It is inexpensive and meets the most demanding OEM spec's in the world. I'd say it is certainly a safe choice.
 
Which engines are common in different parts of the world but still spec xw20 in the US and xw20+ outside the US?

The German engines spec 0w40 in the US.

There isn't too much difference between xw20 and xw30.

There are many who believe that Ford and others spec xw20 in the US for CAFE requirements (and some of those assert that they'd rather use xw30 as a result). But this also suggests there isn't much practical difference between those grades of oil.

Additionally, I do think you generally see higher engine temps outside of the US. Freeway driving at 65mph with big engines is cooler than high speed autobahn driving with turbos and small engines, and in turn cooler than the start stop driving in European cities.
 
Glad you asked.
Every Toyota except the Prius
Nissan
Honda
Most Fords inc all modulars
New Subaru is 20w in the US and 5w30 or other weights elsewhere.

In 194 countries there are no reports of early engine failure or reduced life expectancy due to the oil being too thick in any of these engines.

Yet according to some on this board 0w40 in a Honda 3.5 for example will lead to over pressure, the VVT system will fail and shorter engine life.
None of this is true, many of these engines in other countries have gone 300K+ on this oil.
 
Quote:
Which engines are common in different parts of the world but still spec xw20 in the US and xw20+ outside the US?


Sorry i misunderstood the question. Those engines spec heavier oil in other parts of the world.
Globally its mostly hybrids that spec xw20.

US xW30 maybe close to a heavy 20 but globally xW30 is quite a bit heavier in most areas HTHS 3.5+ Look at GC 0w30 as an example.
Quote:
Additionally, I do think you generally see higher engine temps outside of the US.

85mph on a 100+f day in Texas is going to be pretty hot don't you think?
Temps in the US southern states in the summer are getting hot.
 
So taking into account the rest of the world spec'd a thicker oil than us do those engines last longer than what we see here. What are the reasons for their engine failures compared to what our most common failures are,excluding negligence.
 
The fact that the prius is the only toyota to spec a 20 weight worldwide is in my opinion a big giveaway as to the true purpose of "extreme" light weight oils : MPG.

The sacrifice in order to get this slightly higher mileage is slightly lower oil pressure. On a well maintained and well cared for engine, this is not an issue. But after a couple hundred thousand miles, on an engine that has some some bearing wear, a 30 or 40 weight oil adds a bit more insurance during demanding operating conditions than a 20 weight.

The OEMs know that a 20 weight oil will work perfectly well until their vehicle is out of the warranty period, and probably longer. They know that most people do not use their car's engine to its full potential. They also know that the EPA is breathing down their necks for better MPG. For the mfg it's a no brainer.
 
Last edited by a moderator:
Originally Posted By: Clevy

I'd still like to see the opinions though.


I don't see the 5W-20 as a big issue unless one is in a extreme heat environment or are constantly beating on their engine, which will raise oil temps(there is a reason the high output and turbo engines are now specking 5w30 and even 5W-50)... I use 5W-20 in my mom's car as she just putters around town, oil temp no doubt is seldom over 190*...

North of the border I'd probably use 0/5w-20, at least in the winter but down here south of the Mason-Dixon line it ain't going to happen... The '98 & '07 Grand Marquis both get 5w30(actually the '98 has a quart of 0W-40 in with the 5w30) and the whippin' boy Marauder gets 0W-40... Hot oil pressure on the Marauder is approx 60 psi at 2500 RPMs and 75 psi at 6000 RPMs... In other words maybe 5psi higher than 5W-20 and nowhere near the relief pressure of 95psi... I could likely use WD-40 and make the supposed minimum pressure in that engine...

My old '93 4.6 Mercury got 10W-40 and it's now near 200K mi, runs as quiet as new(I sold it to a friend 2.5 years ago)...
 
Quote:
I don't see the 5W-20 as a big issue unless one is in a extreme heat environment or are constantly beating on their engine, which will raise oil temps(there is a reason the high output and turbo engines are now specking 5w30 and even 5W-50)...

Sure the 20w works okay, its been tested and shown to work in the engines US spec'd for it.
But contrary to some posters opinions on this board its not better because its lighter and doesn't offer any more protection than heavier oils.

I don't have any problems with 20w oils in Per se but what i do have a problem with is this thinner is better being pushed like some sort of twisted religion.

I challenge anyone to name one non hybrid engine that was deigned and built to run strictly on xw20 and nothing heavier. One just one single example.

If there is one it will have to be for a very limited market and not for sale globally.
Excluding the engine from the global market wouldn't make economic sense for the manufacturer would it.
 
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