ENGINE OIL USE

Joined
Jul 13, 2022
Messages
2
Hello Guys!
I have some questions, looking for assistance:
i)Does each engine require specific engine oil viscosity grade?
ii)Does each engine has specific engine oil pump design? How does oil pump design determine oil viscosity grade?
iii)If I use different oil viscosity grade than the one mentioned on the car manual, any effect to the engine performance/life?
iv)For a passenger car don't have VVTI system and operate at 10-to-40-degree Celsius environment condition, any effect if use 0w30/5w30 viscosity grade engine oil?
v)For old truck (run 100k miles), use of more advanced oil(synthetic) could help to extend oil drain interval?
vi)Any effect of use engine oil treatment (STP) to engine performance/life?
vii)If car/truck don’t have manual for oil specifications, how to know which oil to use?
Thanks
 
Joined
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Messages
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Greetings & Welcome

1) Yes but most of todays engines are similar
2) Yes as they are not interchangeable between Mfg's. Engine internal design determine the oil grade to be used by the engineers
3) Most likely not if the oils are close. However there could be damage if you're waaaaay off and dependent on how you drive.
4) Compared to what? 0W20/5W20?...Probably not or not right away. I believe that proper oil change intervals(OCIs) are as important as oil grade.
5) Need more info on the vehicle
6) Most are not needed. Some are snake oils. And they're usually used as a last resort
7) You can look it up. The internet is your friend even if it's not gospel.
 
Joined
Aug 19, 2010
Messages
10,439
Location
Champlain/Hudson Valley
To 23PlanB: I'm not on the welcoming committee but..... WELCOME.

It won't take too much searching to select an acceptable oil for your vehicle/truck but keep #4 of CharBaby's responses in the front of your mind.

Clean is better than dirty. During use, oil will collect and hold dirt in suspension. It will get "dirty" but that is part of its job.
Don't let it get too dirty.
 
Joined
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As a vehicle gets older I wouldn't start extending oil changes, in fact I would do just the opisite and start shortening them but that's just me.
 
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Great questions...

i)Does each engine require specific engine oil viscosity grade?

The oil grade is determined by the minimum oil film thickness necessary. The minimum oil film thickness is determined by 3 main parameters...

- Operating oil temp
- Rod and main bearing clearance
- The load on those bearings

...with other parameters like oil ring tension and hydraulic lifter bleed rate being secondary parameters.

ii)Does each engine has specific engine oil pump design? How does oil pump design determine oil viscosity grade?

There are several oil pump designs from different manufacturers on different engines, but they are all alike in that they are all positive displacement pumps. The pump has little to no impact on the oil grade.

iii)If I use different oil viscosity grade than the one mentioned on the car manual, any effect to the engine performance/life?

That depends on how drastic of a change we are referring to. If the manual calls for a 5W-30, and you use a 5W-40, it's unlikely you'll have any issues. However, if you use a 15W-40 while trying to cold start it in -30°C weather, you're probably going to have a bad time. In some cases, you can even go to a lower oil grade and be okay. I recommend you exercise caution in this regard though. In general, you're better to lean to the excessive side with viscosity rather than the insufficient side.

The recommended oil grade in the manual can be full of compromises like CAFE appeasement and CYA efforts. Sometimes finding the oil grade that best suits your driving style and use of the engine is needed.

iv)For a passenger car don't have VVTI system and operate at 10-to-40-degree Celsius environment condition, any effect if use 0w30/5w30 viscosity grade engine oil?

Abstractly, the only difference between a 0W-30, 5W-30, and 10W-30 is the dynamic (pumping) viscosity in cold weather. The first number represents the lowest temperature at which that oil remains pumpable, hence the "W" stands for winter.

0W-xx = -35°C
5W-xx = -30°C
10W-xx = -25°C
15W-xx = -20°C
20W-xx = -15°C

You can use a 0W-xx or 5W-xx in a climate (and application) that calls for a 10W-xx. However, you cannot run a 10W-xx in a climate that calls for a 5W-xx or 0W-xx.

In a practical sense, a 0W-30 and 5W-30 oil will generally have a lower viscosity initial base oil with more viscosity modifier (in the form of polymers) added to achieve the wider spread. This can make the oil less shear stable and increase the volatility which can lead to more carbon deposits and oil consumption. I tend to only recommend the lower winter grade when it's necessary, and stick with the narrowed spread I can.

v)For old truck (run 100k miles), use of more advanced oil(synthetic) could help to extend oil drain interval?

A synthetic oil will always have a longer service life than conventional counterparts.

vi)Any effect of use engine oil treatment (STP) to engine performance/life?

Only negative effects, for most cases. STP Oil Treatment is a viscous polymer with only a trace of additives. It will increase the viscosity, but will also dilute the additives already in your oil including your anti-wear, anti-friction, detergent, anti-oxidant, and anti-foaming additives. I generally recommend against supplements of any kind. My theory is if you need to add something to your oil, then you need to use a better oil.

vii)If car/truck don’t have manual for oil specifications, how to know which oil to use?

In such cases, I tend to default to a 0W-40. It's a middle of the road grade that is unlikely to cause any harm in any engine.
 
Joined
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Caldwell Idaho
Great questions...



The oil grade is determined by the minimum oil film thickness necessary. The minimum oil film thickness is determined by 3 main parameters...

- Operating oil temp
- Rod and main bearing clearance
- The load on those bearings

...with other parameters like oil ring tension and hydraulic lifter bleed rate being secondary parameters.



There are several oil pump designs from different manufacturers on different engines, but they are all alike in that they are all positive displacement pumps. The pump has little to no impact on the oil grade.



That depends on how drastic of a change we are referring to. If the manual calls for a 5W-30, and you use a 5W-40, it's unlikely you'll have any issues. However, if you use a 15W-40 while trying to cold start it in -30°C weather, you're probably going to have a bad time. In some cases, you can even go to a lower oil grade and be okay. I recommend you exercise caution in this regard though. In general, you're better to lean to the excessive side with viscosity rather than the insufficient side.

The recommended oil grade in the manual can be full of compromises like CAFE appeasement and CYA efforts. Sometimes finding the oil grade that best suits your driving style and use of the engine is needed.



Abstractly, the only difference between a 0W-30, 5W-30, and 10W-30 is the dynamic (pumping) viscosity in cold weather. The first number represents the lowest temperature at which that oil remains pumpable, hence the "W" stands for winter.

0W-xx = -35°C
5W-xx = -30°C
10W-xx = -25°C
15W-xx = -20°C
20W-xx = -15°C

You can use a 0W-xx or 5W-xx in a climate (and application) that calls for a 10W-xx. However, you cannot run a 10W-xx in a climate that calls for a 5W-xx or 0W-xx.

In a practical sense, a 0W-30 and 5W-30 oil will generally have a lower viscosity initial base oil with more viscosity modifier (in the form of polymers) added to achieve the wider spread. This can make the oil less shear stable and increase the volatility which can lead to more carbon deposits and oil consumption. I tend to only recommend the lower winter grade when it's necessary, and stick with the narrowed spread I can.



A synthetic oil will always have a longer service life than conventional counterparts.



Only negative effects, for most cases. STP Oil Treatment is a viscous polymer with only a trace of additives. It will increase the viscosity, but will also dilute the additives already in your oil including your anti-wear, anti-friction, detergent, anti-oxidant, and anti-foaming additives. I generally recommend against supplements of any kind. My theory is if you need to add something to your oil, then you need to use a better oil.



In such cases, I tend to default to a 0W-40. It's a middle of the road grade that is unlikely to cause any harm in any engine.
100% this !
 
Joined
Feb 6, 2021
Messages
1,022
Location
Massachusetts
Hello Guys!
I have some questions, looking for assistance:
i)Does each engine require specific engine oil viscosity grade?
ii)Does each engine has specific engine oil pump design? How does oil pump design determine oil viscosity grade?
iii)If I use different oil viscosity grade than the one mentioned on the car manual, any effect to the engine performance/life?
iv)For a passenger car don't have VVTI system and operate at 10-to-40-degree Celsius environment condition, any effect if use 0w30/5w30 viscosity grade engine oil?
v)For old truck (run 100k miles), use of more advanced oil(synthetic) could help to extend oil drain interval?
vi)Any effect of use engine oil treatment (STP) to engine performance/life?
vii)If car/truck don’t have manual for oil specifications, how to know which oil to use?
Thanks
You can put any viscosity in any engine so long as it 1. has the appropriate winter rating, and 2. Isn't too thin. In that kind of climate where you never see freezing temperatures 15w40 would probably be perfect.

STP is garbage, if you want to use an additive I would recommend only Lubegard, BG MOA or Liquimoly products.
 

OVERKILL

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Great questions...



The oil grade is determined by the minimum oil film thickness necessary. The minimum oil film thickness is determined by 3 main parameters...

- Operating oil temp
- Rod and main bearing clearance
- The load on those bearings

...with other parameters like oil ring tension and hydraulic lifter bleed rate being secondary parameters.



There are several oil pump designs from different manufacturers on different engines, but they are all alike in that they are all positive displacement pumps. The pump has little to no impact on the oil grade.



That depends on how drastic of a change we are referring to. If the manual calls for a 5W-30, and you use a 5W-40, it's unlikely you'll have any issues. However, if you use a 15W-40 while trying to cold start it in -30°C weather, you're probably going to have a bad time. In some cases, you can even go to a lower oil grade and be okay. I recommend you exercise caution in this regard though. In general, you're better to lean to the excessive side with viscosity rather than the insufficient side.

The recommended oil grade in the manual can be full of compromises like CAFE appeasement and CYA efforts. Sometimes finding the oil grade that best suits your driving style and use of the engine is needed.



Abstractly, the only difference between a 0W-30, 5W-30, and 10W-30 is the dynamic (pumping) viscosity in cold weather. The first number represents the lowest temperature at which that oil remains pumpable, hence the "W" stands for winter.

0W-xx = -35°C
5W-xx = -30°C
10W-xx = -25°C
15W-xx = -20°C
20W-xx = -15°C

You can use a 0W-xx or 5W-xx in a climate (and application) that calls for a 10W-xx. However, you cannot run a 10W-xx in a climate that calls for a 5W-xx or 0W-xx.

In a practical sense, a 0W-30 and 5W-30 oil will generally have a lower viscosity initial base oil with more viscosity modifier (in the form of polymers) added to achieve the wider spread. This can make the oil less shear stable and increase the volatility which can lead to more carbon deposits and oil consumption. I tend to only recommend the lower winter grade when it's necessary, and stick with the narrowed spread I can.



A synthetic oil will always have a longer service life than conventional counterparts.



Only negative effects, for most cases. STP Oil Treatment is a viscous polymer with only a trace of additives. It will increase the viscosity, but will also dilute the additives already in your oil including your anti-wear, anti-friction, detergent, anti-oxidant, and anti-foaming additives. I generally recommend against supplements of any kind. My theory is if you need to add something to your oil, then you need to use a better oil.



In such cases, I tend to default to a 0W-40. It's a middle of the road grade that is unlikely to cause any harm in any engine.
Perfectly said! Well, that saves me having to write it, lol! Thanks! 🍻
 
Joined
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Midwest
In such cases, I tend to default to a 0W-40. It's a middle of the road grade that is unlikely to cause any harm in any engine.
If we're talking about Euro oils, I have heard that these could potentially be harmful to catalytic converters in engines where blow-by is already an issue. Do you know how legit a concern this is?
 
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Atlanta,GA
If we're talking about Euro oils, I have heard that these could potentially be harmful to catalytic converters in engines where blow-by is already an issue. Do you know how legit a concern this is?
That's related to the amount of SAPS. Euro oils which reference ACEA Cx (ex, C3,C5, etc) are emissions friendly. Some corresponding Euro certs are BMW LL04, Mercedes 229.51/52, VW 504/507/508/511,. Porsche C20,C30,C40.

Automakers want to make sure the emissions system remains functional for a certain period of time. There has been a lot of pressure on them over emissions.
 

OVERKILL

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Ontario, Canada
That's related to the amount of SAPS. Euro oils which reference ACEA Cx (ex, C3,C5, etc) are emissions friendly. Some corresponding Euro certs are BMW LL04, Mercedes 229.51/52, VW 504/507/508/511,. Porsche C20,C30,C40.

Automakers want to make sure the emissions system remains functional for a certain period of time. There has been a lot of pressure on them over emissions.
Yes, in particular with the more recent fitment of DPF and GPF devices, which are less tolerant.
 

ZeeOSix

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vii)If car/truck don’t have manual for oil specifications, how to know which oil to use?
Google it. Or get on an oil manufactuer's website like Mobil and put the vehicle into their oil matching tool.
 

23PlanB

Thread starter
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You can use a 0W-xx or 5W-xx in a climate (and application) that calls for a 10W-xx. However, you cannot run a 10W-xx in a climate that calls for a 5W-xx or 0W-xx.
Thanks for your reply.
I am located in Dar es Salaam, Tanzania(East Africa). It is very rarely for a ambient temperature to go below 5 Celsius in many part on the country. Most of the passenger car(other trucks) are second hand purchased.
-Many passenger car are using 20W50 SL, Going for 5W30 viscosity grade (API SN) may result to any engine problem? I am trying to improving drain interval.
-For old truck (really old 1990s) are using SAE 40 viscosity grade, any issue to the engine if start to shift to use of multigrade grade with either less/high viscosity grade,?
 

ZeeOSix

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For old truck (really old 1990s) are using SAE 40 viscosity grade, any issue to the engine if start to shift to use of multigrade grade with either less/high viscosity grade,?
So you are now using straight SAE 40?

If you want a 40 in multi-grade, use a 10W-40 if it never gets below 5C there.
 
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