Oil grade vs pressure vs volume

[OVERKILL]

Originally Posted By: morris
the factory putting an oil cooler on an engine. makes me think they are trying to cover a deficient design.


My M5 has an oil cooler.

What makes it's design deficient? It is designed to cruise at 190Mph @ 7,000RPM.

The thermostatically controlled oil cooler is there to keep the oil temperature in check. That's part of a good design, not a deficiency.

My Expedition has an oil cooler. It has an 8,000lb towing capacity. It also has a trans and PS cooler. Ford put them on there to control the temperatures during HD usage. Again, I wouldn't call that a deficiency, I would call that smart thinking on behalf of the manufacturer.

 

[MarkStock]

Originally Posted By: Trav
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.


That's why I used the word "generally".

In the case of Texas, there is only one road that's legally 85mph. Now where I live in CA, it does occassionally get to 100f as well, and I have a Mercedes 5.5 that runs at 2400 revs at 85mph. My coolant temp stays lower in those conditions than stop start conditions. I think airflow at higher speeds makes a difference.

I also think that there is not much difference between a 20 weight oil and a 30 weight oil due to improvements in oil. I think the oil of yesteryear might have had a problem in 20 weight but once major manufacturers signalled they wanted to go to that weight (in the US for fuel economy reasons), got the oil manufacturers to meet their spec requirements, and then tested that oil, 20 weight oil became accepted.

My 2004 Ford has 5w20 on the cap, so it's been around for a while and gained acceptance.

Now in Europe and elsewhere, they haven't necessarily carried out the field testing on 20 weight oil. Perhaps that's the reason they don't spec it.

Additionally, there is nothing legislatively pushing anyone towards 20 weight. So why would the manufacturer's spend money on field testing and ask oil suppliers to change their supply chain when there is no need?

All that would happen is that you'd see endless arguments on jurgenistheoilguy.de forums about 5w20 vs 5w30 and what color bottle is Austrian Castrol.

 

[Trav]

Quote:
So why would the manufacturer's spend money on field testing and ask oil suppliers to change their supply chain when there is no need?

CAFE, The answer is that simple.

Its not that 20w oil has not been tested in other countries or it would not be available if speced.
It has been tested in Europe and showed no real performance benefits over xW30 to start specing it for normal driving conditions.

Like i said show me one engine that is spec for xW20 only and tell me why the vast majority of the worlds countries are wrong by not using it.
There is no "need" for 20w oil in any conditions other than extreme cold.
Are you running 20w in the MB? Why not if there is little or no difference between 20w and 30w?

 

[MarkStock]

Originally Posted By: Trav
Quote:
So why would the manufacturer's spend money on field testing and ask oil suppliers to change their supply chain when there is no need?

CAFE, The answer is that simple.


I meant for non CAFE countries.

 

[MarkStock]

Originally Posted By: Trav
Are you running 20w in the MB? Why not if there is little or no difference between 20w and 30w?


I'm following Mercedes recommendations / requirements. And they generally recommend 40w with a couple of heavier 30w. So I wouldn't want to do anything they don't recommend and 20w is a little far away from the weight range they recommend.

In my Ford, I do run 5w30 because I got it for a $ a quart and I had read it was initially the spec for the engine I have before Ford moved to 5w20. But prior to 5w30, I had the dealer put in what they recommended which was (and still is) Motorcraft 5w20.

 

[cchase]

I have been surprised to notice that my oil pressure is routinely 5-10 psi higher at all temperatures with Mobil 1 0w40 over Mobil 1 5w30.

More things to think about.

 

[OVERKILL]

Originally Posted By: cchase
I have been surprised to notice that my oil pressure is routinely 5-10 psi higher at all temperatures with Mobil 1 0w40 over Mobil 1 5w30.

More things to think about.


Why is that surprising? It is a heavier oil with a higher HTHS

 

[CATERHAM]

Originally Posted By: Clevy
Ya. Overkill. I almost hate to admit that Mobil's 0w-40 might be ideal for my particular application.
Darn.

Once you install your oil gauges the first thing you're going to find is that the spec' 5W-20 is a plenty thick motor oil. Since you engine has an oil cooler, maximum oil temp's will very likely be well contained even during aggressive driving during the heat of summer and therefore it will be still unlikely that you'll be testing the factory OP spec's.
I'm able to run a 20wt oil in my track car for that very reason; oil temp's are kept low, generally under 100C. Running an ultra high VI oil I've optimized the HTHSV to be in the 2.7-2.8cP range.

Plenty of Mustangs run the spec' 5W-20 at the track without a problem. The issue at a road race track is that you have a series of 20-30 minute track sessions with the engine often cooling down completely between sessions. When your session starts few drivers wait for more than a lap before "giving it the beans" and even the lightest, highest VI 0W-20 is still way too thick for at least the first 10 minutes of the session until some heat has built-up in the oil thinning it out.
Running a very much heavier oil, even a high VI oil like Mobil 1 0W-40, it may only be the last couple of minutes of the track session that you are able to use maximum rev's without the oil pump remaining in by-pass; a clear indication of an oil too heavy for the application.

The ideal oil viscosity at the track comes form some experimenting but it will be a high VI oil that still provides the minimum required oil pressure at the end of a track session when the oil is as hot as it will ever get.

 

[Clevy]

Thanks caterham. I think the stock block by-pass is 90 pounds. The 4v can handle 7500rpms before valve float becomes a possibility. I haven't seen a stock dyno sheet for awhile but I think the hp peak is around 6500rpms. I am getting it dynotuned because I've ported the intake,headers and prochamber,intake spacer. These engines came under-rated at 305 and they typically dyno at around 300rwhp.
I am going to try your thin idea next spring while temps are still warming up,then a used oil analysis to see how it's wearing and whether or not it's wearing according to averages,then make a choice from there as far as oil brand and grade. Then another used oil analysis to see if there is a difference. Then pick an oil to stick with.
Ive got a lot of liqui-moly 0w-40. I think I will buy their 5w-20 to thin the thicker stuff,and go from there.
Thanks for everyones input.
Great discussion. Keep er going

 

[CATERHAM]

Clevy, if you've got lots of LM 0W-40 I'd suggest blending with a high VI 0W-20 like the Toyota 0W-20 (216 VI) or the high moly Honda/Acura 0W-20 (197 VI). This will maximize the resulting VI of the oil as well as the HTHSV for a given OP level.

 

[OVERKILL]

I'd start at the 0w40 and go down, JMHO. Ford spec's 5w50 for the BOSS 302. Yes, it makes more power, but it is still a modular, designed to be tracked.

 

[mechtech2]

Originally Posted By: Clevy
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......


Thinner oil? Not much out there that is thinner!
Just use the 5-20 or 0-20 and be happy.

 

[cchase]

Originally Posted By: OVERK1LL
Originally Posted By: cchase
I have been surprised to notice that my oil pressure is routinely 5-10 psi higher at all temperatures with Mobil 1 0w40 over Mobil 1 5w30.

More things to think about.


Why is that surprising? It is a heavier oil with a higher HTHS

Surprised, probably not my best word choice. But it's something for people to consider as some feel that any 0w is thinner at start-up than any 5w oil.

 

[OVERKILL]

Originally Posted By: cchase
Originally Posted By: OVERK1LL
Originally Posted By: cchase
I have been surprised to notice that my oil pressure is routinely 5-10 psi higher at all temperatures with Mobil 1 0w40 over Mobil 1 5w30.

More things to think about.


Why is that surprising? It is a heavier oil with a higher HTHS

Surprised, probably not my best word choice. But it's something for people to consider as some feel that any 0w is thinner at start-up than any 5w oil.


Gotcha, yes, many don't quite understand that part properly.

 

[SteveSRT8]

Originally Posted By: OVERK1LL
I'd start at the 0w40 and go down, JMHO. Ford spec's 5w50 for the BOSS 302. Yes, it makes more power, but it is still a modular, designed to be tracked.


The Mobil 1 0W-40 is quite an oil. I am consistently impressed by its performance in the most demanding operating conditions.

 

[JOD]

Originally Posted By: Trav

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.


You're making an argument that doesn't exist. Combustion engines are pretty tolerant of oil viscosity; if they weren't, there would be massive failures of all combustion engines since many spend much of their lives pushing around oil that is MUCH thicker, by several orders of magnitude, than 20W50. Cars don't fail while they're getting up to operating temperature, so your argument is a total strawman. The discussion isn't about "preventing your engine from failing", it's about "what's optimal".

If you want to base your choice based on what oil in used in Namibia or Nonamistan, be my guest. I'm glad we have more option here.

 

[Trav]

Who is talking about 20w50?
Quote:
Combustion engines are pretty tolerant of oil viscosity; if they weren't, there would be massive failures of all combustion engines since many spend much of their lives pushing around oil that is MUCH thicker

Thank you. That is exactly my point.

The vast majority of countries globally spec xw30 with an HTHS of 3.5+ or xw40. in even the most sedate grocery getters.

Its no strawman argument its a legitimate question.
Only 3 countries spec 20w for engines the that are spec for xW30 or xW40 everywhere else in the world. WHY?
Apparently 20w is not optimal in anything globally. Engines maybe able survive on it but that's not optimal is it?

Anyone reading this forum for longer than a few days has read post by some who claim that using anything but xW20 can damage cam phasers, block piston squirter's, and so on in an engine spec for 20w.
Fact is there is no engine spec'd specificity for 20w.

 

[mechtech2]

JOD -
You are AGREEING with Trav. It makes no sense to condemn him.

 

[Trav]

Quote:
I'd start at the 0w40 and go down, JMHO. Ford spec's 5w50 for the BOSS 302. Yes, it makes more power, but it is still a modular, designed to be tracked.

Heck no that would just make too much sense.
Originally Posted By: Caterham
Clevy, if you've got lots of LM 0W-40 I'd suggest blending with a high VI 0W-20 like the Toyota 0W-20 (216 VI) or the high moly Honda/Acura 0W-20 (197 VI).

This goes against what the other expert claims.
Originally Posted By: AEHaas
I wanted to get every speck of the Shell oil out of there. For optimal results you are not supposed to mix synthetic oils of different brands.

In this case Caterham is 100% correct IMHO.
The point is on a forum there are 100 diffeent opinions and each one is based different experiences.
Use the one that fits closest to your situation. If you are going to track this car Overkill's recommendation makes good sense as does his reasoning.