Besides G-Man and myself is there anyone using single weight engine oil in moderate climate? I have posted threads about myself and two other people using single weight oil, one an older flathead Cadillac and a vehicle that could be considered as opposite as can be, a Honda Fit. Everything about these two cars is as different as two cars can be. In my situation it's a 510 with over half a million miles and not much fix it repair work. Those that I've talked to assure me that single weight oil is not only the wrong choice but that dire consequences will develop because of it, and no one wants dire consequences to happen to their ride, do they? Could it be that the real success of synthetic oil is that many formulations do not have VII's? If VII's are good and don't hamper the lubrication process then why don't we see a 0w-50 or a -20w-30 or why not make every 5w30 a 0w-30? Why not if VII's don't get in the way of lubrication? And are these 5w-20's better oil regardless of the viscosity because they cover a smaller spread of viscosity range? Would a modern 20w-20 say a Group III oil be a super oil? I've been reading about BioSyn oil and how there is a super secret blend of 5w-40 oil made up in small batches being tested by an engineer with real abilities to analyze data? Could the BioSyn company brew up a 20w-20 oil that would be a real performer in daily drivers? Maybe a BioSyn 20w-20 could be the next great thing in engine oil? Sorry about asking too many questions but I'd like to know your thoughts.
is there anyone out there using single weight oil?
- Thread starter BarkerMan
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No. It's just another ridiculous BITOG fad IMO and something else to obsess over, no offense. Sure having less VII's is better in theory, but it depends. VII's are actually beneficial in some cases, according to some, but that has been completely ignored on here. You also have to realize that with synthetics, very little VII's are needed. Your top tier brands use very good VII's and shearing is not an issue. The top 2 brands in NASCAR both use some small amount of VII's. I've been told having "some" is better than having "none".
*Engines are not failing due to VII's in PCMO. In fact, engines are lasting longer than ever. The latest API specs and requirements called for by your owners manual is all you need. IMHO. I am not against straight grades at all. I just don't think it matters in most cars. For maximum shear stability/racing, I think using little to none is ideal. This is why most good motorcycle oils and oils like Redline use ZERO VII's.
From Molekule:
Quote:
Actully, all of them, since fuel dilution will reduce viscosity, the VII's help there, the fuel attempts to soot up the oil, so Detergents/ Dispersants help there, the FM's help the oil maintain lubricity, the antoxidants retard oxidation, etc., etc.
molakule, can sheared up VII's also have some FM or AW ability? or are the little pieces worthless at that point? Just fishing for an upside on the VII that seem to get bad rap often around here.
Yes. A tribochemical text on the subject of VII's and Blending has shown that VII's do show some FM and AW qualites.
Some VII's can have dispersant as well as VI improvement compounds contained therein.
VII compounds are much improved over the black-sludge days and are now multifunctional.
*Engines are not failing due to VII's in PCMO. In fact, engines are lasting longer than ever. The latest API specs and requirements called for by your owners manual is all you need. IMHO. I am not against straight grades at all. I just don't think it matters in most cars. For maximum shear stability/racing, I think using little to none is ideal. This is why most good motorcycle oils and oils like Redline use ZERO VII's.
From Molekule:
Quote:
Actully, all of them, since fuel dilution will reduce viscosity, the VII's help there, the fuel attempts to soot up the oil, so Detergents/ Dispersants help there, the FM's help the oil maintain lubricity, the antoxidants retard oxidation, etc., etc.
molakule, can sheared up VII's also have some FM or AW ability? or are the little pieces worthless at that point? Just fishing for an upside on the VII that seem to get bad rap often around here.
Yes. A tribochemical text on the subject of VII's and Blending has shown that VII's do show some FM and AW qualites.
Some VII's can have dispersant as well as VI improvement compounds contained therein.
VII compounds are much improved over the black-sludge days and are now multifunctional.
I use and recommend straight grade oils all the time. Especially when they carry a multigrade rating without the VII's.
It's simple economics. It cost less to make these oils, so you can get more benefit from it.
It's simple economics. It cost less to make these oils, so you can get more benefit from it.
buster - Well said.
In my lawnmower, definitely.
In my cars, nah. I've selected multigrades (GC and Rotella 15W40) with very strong HT/HS ratings, and with good enough basestocks so as to need as little VII as possible. I think those two criteria are what is really important. Oh, and they have good add packs.
- Scott
In my cars, nah. I've selected multigrades (GC and Rotella 15W40) with very strong HT/HS ratings, and with good enough basestocks so as to need as little VII as possible. I think those two criteria are what is really important. Oh, and they have good add packs.
- Scott
Won't you get *slightly* better gas mileage in most cars if you use 5w30 verses SAE 30 ??
I've owned a 69 911S Porsche for many years. I use straight 30w in it - always have and always will. Reason: It works (the bottom end of my motor was in great shape when I rebuilt it) and I was told by several Porsche mechanics/racers over the years to keep a straight wieght oil in the early cars.
Now, before I'm labeled as a "pro-straight oil" guy, My wife & I also have a relatively new Chrysler Sebring conv. (2.7 sludgger motor) and a '97 Ford Aspire (my beater.) These two cars both get multi-grades usually 10-30 but I've put 5-30 in the Sebring. As you all know, the older Porsche motors are a very different breed, with high temps/hotspots; high revving, etc. so I stay with what has proven to work in that car.
Just my .02
Bill.
Now, before I'm labeled as a "pro-straight oil" guy, My wife & I also have a relatively new Chrysler Sebring conv. (2.7 sludgger motor) and a '97 Ford Aspire (my beater.) These two cars both get multi-grades usually 10-30 but I've put 5-30 in the Sebring. As you all know, the older Porsche motors are a very different breed, with high temps/hotspots; high revving, etc. so I stay with what has proven to work in that car.
Just my .02
Bill.
My 510 is modified for better mileage but with 30w I'm getting 45-46 mpg. I drive carefully and stay off the brake pedal and anyone can improve their mileage with a little work. I hate traffic and make a game out of driving as smooth as I can. On the road is the wrong place to make up time. I am not convinced that lower viscosity oil in a high mileage engine makes for better mileage. I drive just fast enough to keep out of the way of more important people that are in a hurry or talking on the phone. My cruise control is a hand throttle that I made to hold the carburetor fixed. If you hit the brake it knocks the linkage of the notch and you have to reset it. It's not as fancy as modern electronic ones but it does a decent job and has yet to fail. Single weight oil in the right place is a good lubrication solution but the common knowledge is that the only way to go is multi-grade oil.
The guy that bought the Fit let me put a boroscope down the spark plug holes. There is evidence of hone marks, faint but still there. The pistons look very good and there is no erosion between the head and block. The oil is doing its job.
Buster's remarks are well taken. Engines are so good today that the failure mode of a modern car is style, rust, electrical system and many other components long before the engine.
I still think that any oil benefits from fewer VII's and that may be why synthetic oil may perform better when stressed.
Buster's remarks are well taken. Engines are so good today that the failure mode of a modern car is style, rust, electrical system and many other components long before the engine.
I still think that any oil benefits from fewer VII's and that may be why synthetic oil may perform better when stressed.
a little VII will bump the HTHS where base oil vis along "runs out of gas"
bruce
bruce
""how much of the HTHS is determined by the base oil and the VII ?""
good question I have no answer tho using the blend computers you can see that a small amount of VII will boost the HTHS with out hurting the low end CCS where to get same HTHS with a higher base oil CCS will suffer.
""Is there a crossover point where the HTHS can be less than the base oil viscosity ?"'
Do not understand? the HTHS will be no lower than base oil alone
and with VII will be higher than base oil alone.
bruce
good question I have no answer tho using the blend computers you can see that a small amount of VII will boost the HTHS with out hurting the low end CCS where to get same HTHS with a higher base oil CCS will suffer.
""Is there a crossover point where the HTHS can be less than the base oil viscosity ?"'
Do not understand? the HTHS will be no lower than base oil alone
and with VII will be higher than base oil alone.
bruce
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Sorry, the question was ill conceived.
So the VIIs always produce an increase in HTHS with increasing percentage.
When the poorer VIIs shear/chop up whatever, then you are left with (at worst) the base viscosity...possibly a 20 weight when you bought a 30 or 40.
Is that correct ?
So the VIIs always produce an increase in HTHS with increasing percentage.
When the poorer VIIs shear/chop up whatever, then you are left with (at worst) the base viscosity...possibly a 20 weight when you bought a 30 or 40.
Is that correct ?
HTHS is measured at a fixed temperature and fixed shear rate. What of conditions in the engine that exceed the severity of the test conditions?
If VI improvers are designed to approximate the HTHS of a Newtonian oil under the conditions of the HTHS test, I am of the opinion that if you push a VI laden oil more severely than what the HTHS test simulates, it will have a lower HTHS than an oil with no VI improvers.
If VI improvers are designed to approximate the HTHS of a Newtonian oil under the conditions of the HTHS test, I am of the opinion that if you push a VI laden oil more severely than what the HTHS test simulates, it will have a lower HTHS than an oil with no VI improvers.
Originally Posted By: Shannow
Sorry, the question was ill conceived.
So the VIIs always produce an increase in HTHS with increasing percentage.
When the poorer VIIs shear/chop up whatever, then you are left with (at worst) the base viscosity...possibly a 20 weight when you bought a 30 or 40.
Is that correct ?
Thats correct
bruce
Sorry, the question was ill conceived.
So the VIIs always produce an increase in HTHS with increasing percentage.
When the poorer VIIs shear/chop up whatever, then you are left with (at worst) the base viscosity...possibly a 20 weight when you bought a 30 or 40.
Is that correct ?
Thats correct
bruce
Originally Posted By: G-MAN
HTHS is measured at a fixed temperature and fixed shear rate. What of conditions in the engine that exceed the severity of the test conditions?
If VI improvers are designed to approximate the HTHS of a Newtonian oil under the conditions of the HTHS test, I am of the opinion that if you push a VI laden oil more severely than what the HTHS test simulates, it will have a lower HTHS than an oil with no VI improvers.
No not any lower than the base oil vis that you start with unless the base stock is sheared, all you can lose is the VII vis kick and normally you may lose about 50-70% of that.
SSI or shear stability index is a mesurment of vis loss from the potion of vis increase that the VII gives.
a 50% SSI will mena if a VII gives say a 6 cSt increase in vis that after the shear test 3 Cst or 50% of the increase will be lost due to shear.
bruce
HTHS is measured at a fixed temperature and fixed shear rate. What of conditions in the engine that exceed the severity of the test conditions?
If VI improvers are designed to approximate the HTHS of a Newtonian oil under the conditions of the HTHS test, I am of the opinion that if you push a VI laden oil more severely than what the HTHS test simulates, it will have a lower HTHS than an oil with no VI improvers.
No not any lower than the base oil vis that you start with unless the base stock is sheared, all you can lose is the VII vis kick and normally you may lose about 50-70% of that.
SSI or shear stability index is a mesurment of vis loss from the potion of vis increase that the VII gives.
a 50% SSI will mena if a VII gives say a 6 cSt increase in vis that after the shear test 3 Cst or 50% of the increase will be lost due to shear.
bruce
Back to the original question.
I live in Sandy Eggo where my garaged car sees a minimum low of about 50F in the winter and an average low of 65F in the summer. I'll use 10W-30 in the winter and SAE-30 in the summer. Regardless of oil, I ALWAYS drive easy and keep the RPM between 1500 and 2000 for the first five minutes of driving.
When I use 10W-30, the car will consume 1 quart of oil between 5000-mile oil changes. When I use SAE-30, the car will consume less than 1/2 a quart during that same period. The engine is also a little quieter with the SAE-30. Lower oil consumption and quieter running - there has to be a reason for that.
There is nothing more robust that a straight weight oil. They're shear-stable and don't contain VI improvers that can turn to engine varnish as they degrade.
I live in Sandy Eggo where my garaged car sees a minimum low of about 50F in the winter and an average low of 65F in the summer. I'll use 10W-30 in the winter and SAE-30 in the summer. Regardless of oil, I ALWAYS drive easy and keep the RPM between 1500 and 2000 for the first five minutes of driving.
When I use 10W-30, the car will consume 1 quart of oil between 5000-mile oil changes. When I use SAE-30, the car will consume less than 1/2 a quart during that same period. The engine is also a little quieter with the SAE-30. Lower oil consumption and quieter running - there has to be a reason for that.
There is nothing more robust that a straight weight oil. They're shear-stable and don't contain VI improvers that can turn to engine varnish as they degrade.
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