I read forums on this website looking for information in order to pick the best oil for my new Honda. I have noticed when there is a dicussion about 5W20 weight conventional oils someone usually mentions that some brands are thicker than others. I'm no scientist but if the weight is 5W20, shouldn't they all have the same viscosity? Is viscosity the property of whether an oil is thicker or thinner? I like GTX but if it's thicker than the others maybe it will not protect the engine as well during cold start-up as a thinner 5W20.
Why are some 5W20 oils thicker than others?
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SAE visc is a range, not an exact figure. Most 30s are on the very thin end of 30, about 10cSt. SAE 20 is on the high end of 20, 8-9cSt. There is overlap when a 30 shears down to a 20. 20s are made with a base oil that makes for minimal shear, that's how they control wear compared to a 30.
Blenders adjust visc and additives to account for shearing, plus to minimize wear. A thin 20 like Havoline will tend not to shear, and keep wear down. I don't know everything about 20 weights, but I have and use a lot of Havoline. Motorcraft (Conoco) is another good 20 weight.
Blenders adjust visc and additives to account for shearing, plus to minimize wear. A thin 20 like Havoline will tend not to shear, and keep wear down. I don't know everything about 20 weights, but I have and use a lot of Havoline. Motorcraft (Conoco) is another good 20 weight.
There is a viscosity range that oil's have. But to be listed as an 5w-20 vs another 5w-20 the slight viscosity differance really does not matter in the real world. GTX is the thickest 5w-20 of off the self convental motor oils. But GTX has an "habit" of shearing more than other 5W-20's. It is just a question how each oil is formulated.
I have a 2008 CR-V EX.
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Quote:
Why are some 5W20 oils thicker than others?
I always wondered why some 5w20 oils were thinner than others
Why are some 5W20 oils thicker than others?
I always wondered why some 5w20 oils were thinner than others
Originally Posted By: Gary Allan
Quote:
Why are some 5W20 oils thicker than others?
I always wondered why some 5w20 oils were thinner than others
I wonder if anyone wonders about the ones right in the middle.
Quote:
Why are some 5W20 oils thicker than others?
I always wondered why some 5w20 oils were thinner than others
I wonder if anyone wonders about the ones right in the middle.
Whoa, my first post! Been lurking and learning for a while...
I apologize if this post is a bit off-topic.
It appears that some oils are simply a bit thicker or thinner than others...but, you have to decide if that matters.
For me, it does.
My wife has a Honda CR-V which requires 5w20 oil. In my research I found that some of them don't meet the GM6094M spec. We live in Michigan (very cold winters), so I prefer that an oil have good flow in the winter.
I usually use synthetic (M1), but want to save some money because we are expecting a baby in a few months.
I have tested Castrol GTX for the past few months in my own car (5w30), and it has been quite good. However, I did notice that it takes substantially longer for my oil pressure light to go out. It obviously does not flow as well as the M1 when cold.
I considered the GTX for the Honda, but it does not meet the GM spec (the 5w30 barely meets the spec, but the 5w20 is surprisingly thick).
So, I bought regular old Pennzoil on sale, as it seems to turn in good used oil analysis and easily meets the GM spec (and many others).
So, I will end up using up my stash of Pennzoil Platinum and M1 for winter, then move over to the Pennzoil ($8/gallon!) year-round.
Doing 6 month/5k mile oil changes, I will be changing the oil in three cars (mine, my wife's and my mom-in-law's) for $36/year.
As a related side-note, I am getting conflicting info on whether 5w30 can be used in the Honda. I cannot understand why there would be an issue, but I did find some info stating that the thicker oil goofed up the engine management sensors on certain Honda engines (as an ex-master mechanic, I find this hard to believe).
I apologize if this post is a bit off-topic.
It appears that some oils are simply a bit thicker or thinner than others...but, you have to decide if that matters.
For me, it does.
My wife has a Honda CR-V which requires 5w20 oil. In my research I found that some of them don't meet the GM6094M spec. We live in Michigan (very cold winters), so I prefer that an oil have good flow in the winter.
I usually use synthetic (M1), but want to save some money because we are expecting a baby in a few months.
I have tested Castrol GTX for the past few months in my own car (5w30), and it has been quite good. However, I did notice that it takes substantially longer for my oil pressure light to go out. It obviously does not flow as well as the M1 when cold.
I considered the GTX for the Honda, but it does not meet the GM spec (the 5w30 barely meets the spec, but the 5w20 is surprisingly thick).
So, I bought regular old Pennzoil on sale, as it seems to turn in good used oil analysis and easily meets the GM spec (and many others).
So, I will end up using up my stash of Pennzoil Platinum and M1 for winter, then move over to the Pennzoil ($8/gallon!) year-round.
Doing 6 month/5k mile oil changes, I will be changing the oil in three cars (mine, my wife's and my mom-in-law's) for $36/year.
As a related side-note, I am getting conflicting info on whether 5w30 can be used in the Honda. I cannot understand why there would be an issue, but I did find some info stating that the thicker oil goofed up the engine management sensors on certain Honda engines (as an ex-master mechanic, I find this hard to believe).
Loogie,
to BITOG! And congrats on the baby! Where at in Michigan are you located? And I've never heard of using 5w30 in a newer Honda causing issues, even if 5W-20 is recommended.. I wouldn't think it would cause any issues.
Look up the used oil analysis on the Xw/20 oils in the used oil analysis section and study up on the wear numbers.
Originally Posted By: Audi Junkie
SAE visc is a range, not an exact figure. Most 30s are on the very thin end of 30, about 10cSt. SAE 20 is on the high end of 20, 8-9cSt. There is overlap when a 30 shears down to a 20. 20s are made with a base oil that makes for minimal shear, that's how they control wear compared to a 30.
Blenders adjust visc and additives to account for shearing, plus to minimize wear. A thin 20 like Havoline will tend not to shear, and keep wear down. I don't know everything about 20 weights, but I have and use a lot of Havoline. Motorcraft (Conoco) is another good 20 weight.
I also use a CP oil that is a cousin of MC(which I used first after breaking in my 2006 Accord V6 at 21,500 miles on the ODO), the allmighty CP Super Allseason Synthetic Blend and it is a great oil. I get great gas mileage because it is slicker(don't ask ot you will be pile drove 'round here) Whether it is thinner, the numbers don't show any difference from say any other competitive synthetic blends out there.
(ohh and btw, I would seriously consider using the Havoline oil to 'break-in' my car as it is pretty good Conventional oil)
(I, personally, used Exxon Mobil's Drive clean 5000 then DC 7500 TWICE before the aforementioned Motorcraft at 21,500 miles)
(Man, I am down to fewer then 4.5 quarts to do my next oil change and my MMS is allready down to 30%. Gotta head to the Distribution Center in Spring Branch to 'make my new stash happen'!)
SAE visc is a range, not an exact figure. Most 30s are on the very thin end of 30, about 10cSt. SAE 20 is on the high end of 20, 8-9cSt. There is overlap when a 30 shears down to a 20. 20s are made with a base oil that makes for minimal shear, that's how they control wear compared to a 30.
Blenders adjust visc and additives to account for shearing, plus to minimize wear. A thin 20 like Havoline will tend not to shear, and keep wear down. I don't know everything about 20 weights, but I have and use a lot of Havoline. Motorcraft (Conoco) is another good 20 weight.
I also use a CP oil that is a cousin of MC(which I used first after breaking in my 2006 Accord V6 at 21,500 miles on the ODO), the allmighty CP Super Allseason Synthetic Blend and it is a great oil. I get great gas mileage because it is slicker(don't ask ot you will be pile drove 'round here) Whether it is thinner, the numbers don't show any difference from say any other competitive synthetic blends out there.
(ohh and btw, I would seriously consider using the Havoline oil to 'break-in' my car as it is pretty good Conventional oil)
(I, personally, used Exxon Mobil's Drive clean 5000 then DC 7500 TWICE before the aforementioned Motorcraft at 21,500 miles)
(Man, I am down to fewer then 4.5 quarts to do my next oil change and my MMS is allready down to 30%. Gotta head to the Distribution Center in Spring Branch to 'make my new stash happen'!)
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Originally Posted By: Loogie
As a related side-note, I am getting conflicting info on whether 5w30 can be used in the Honda. I cannot understand why there would be an issue, but I did find some info stating that the thicker oil goofed up the engine management sensors on certain Honda engines (as an ex-master mechanic, I find this hard to believe).
Some engines use hydraulic pressure to control cam timing. I've read that some of these engines are sensitive to oil viscosity, and too thick of an oil can adversely affect operation.
As a related side-note, I am getting conflicting info on whether 5w30 can be used in the Honda. I cannot understand why there would be an issue, but I did find some info stating that the thicker oil goofed up the engine management sensors on certain Honda engines (as an ex-master mechanic, I find this hard to believe).
Some engines use hydraulic pressure to control cam timing. I've read that some of these engines are sensitive to oil viscosity, and too thick of an oil can adversely affect operation.
I started this topic after looking for weeks on this forum. This forum has so much good information. The problem for me is that all of this information overload has caused me to question my lifetime commitment to using Castrol GTX in everything that I have ever owned. Now since I have a new Honda that requires 5W20 oil I question it more. Stumbling on GM specifications list that did not include GTX, looking at used oil analysis, and reading what others have to say about oils they use has me thinking of changing brands, types(synthetic or conventional) or both. I have never had issues with GTX but I want the best for my CR-V. I still have the factory fill and 4000 miles on it. OCI will be 5,000 miles. So far, I am considering Motorcraft blend, Pennzoil yellow, Pennzoil Plat. and Mobil Clean 5000. I got about 1000 miles left before I need to decide on one. HELP!!!
I think your CR-V has the same 2.4 motor as my '04 Accord doesn't it? I've used GTX 5w30 without problem. In fact, my current fill is with GC 0w30 which is even thicker and it runs just fine. Fuel economy hasn't changed on the GC so I'm happy about that!
Yes, it is a 2.4 engine. So you think the 0W30 Castrol would work for me. I was kinda scared of using any zero weight oil in the Honda.
Originally Posted By: bigalw
Yes, it is a 2.4 engine. So you think the 0W30 Castrol would work for me. I was kinda scared of using any zero weight oil in the Honda.
Dont think of it that way. "0W" is just a specification 0W30 Castrol meets. 0/30 castrol is actually pretty thick and is border line /40 when hot and as far as cold temperatures; it is pretty thick when cold, much thicker than hot. Even a 0W20 is much thicker cold than hot.
Yes, it is a 2.4 engine. So you think the 0W30 Castrol would work for me. I was kinda scared of using any zero weight oil in the Honda.
Dont think of it that way. "0W" is just a specification 0W30 Castrol meets. 0/30 castrol is actually pretty thick and is border line /40 when hot and as far as cold temperatures; it is pretty thick when cold, much thicker than hot. Even a 0W20 is much thicker cold than hot.
Originally Posted By: ThirdeYe
Loogie,
to BITOG! And congrats on the baby! Where at in Michigan are you located? And I've never heard of using 5w30 in a newer Honda causing issues, even if 5W-20 is recommended.. I wouldn't think it would cause any issues.
Thanks ThirdeYe!
I am just outside Ann Arbor.
I know...the 5w30 thing was odd. It probably will not make any difference (however, a poster above noted that viscosity could have an effect upon the management system, and this dovetails with what I read in other forums).
To the person worried about GTX, you probably have nothing to worry about. It seems like an excellent oil. In fact, I will use it in the CR-V for the summer (I got it on sale), and have no concerns about protection. My only concern (which may be minor and unnecessary) is the cold flow properties.
Interestingly, the GTX in my Monte Carlo seems to have remained cleaner than the M1. I know that this doesn't necessarily indicate any particular advantage/disadvantage, but I kinda like seeing a cleaner dipstick. "Only a used oil analysis will tell."
By the way, this is a very cool site. I like the tone of the posters here: fairly positive.
I will "reintroduce" myself, probably in the General forum.
Loogie,
Thanks ThirdeYe!
I am just outside Ann Arbor.
I know...the 5w30 thing was odd. It probably will not make any difference (however, a poster above noted that viscosity could have an effect upon the management system, and this dovetails with what I read in other forums).
To the person worried about GTX, you probably have nothing to worry about. It seems like an excellent oil. In fact, I will use it in the CR-V for the summer (I got it on sale), and have no concerns about protection. My only concern (which may be minor and unnecessary) is the cold flow properties.
Interestingly, the GTX in my Monte Carlo seems to have remained cleaner than the M1. I know that this doesn't necessarily indicate any particular advantage/disadvantage, but I kinda like seeing a cleaner dipstick. "Only a used oil analysis will tell."
By the way, this is a very cool site. I like the tone of the posters here: fairly positive.
I will "reintroduce" myself, probably in the General forum.
Originally Posted By: bigalw
I started this topic after looking for weeks on this forum. This forum has so much good information. The problem for me is that all of this information overload has caused me to question my lifetime commitment to using Castrol GTX in everything that I have ever owned. Now since I have a new Honda that requires 5W20 oil I question it more. Stumbling on GM specifications list that did not include GTX, looking at used oil analysis, and reading what others have to say about oils they use has me thinking of changing brands, types(synthetic or conventional) or both. I have never had issues with GTX but I want the best for my CR-V. I still have the factory fill and 4000 miles on it. OCI will be 5,000 miles. So far, I am considering Motorcraft blend, Pennzoil yellow, Pennzoil Plat. and Mobil Clean 5000. I got about 1000 miles left before I need to decide on one. HELP!!!
For your Honda, I would recommend the Mobil 5000 for sure! Better yet, if you absolutely must switch to 'some kind of synthetic', go with the Mobil Drive Clean 7500!! You won't be disappointed either way and your Honda will love you for using the same or very similar oil to break-in oil!
(I believe both of these oils can be had at closeout prices these days..yes, the pricing has even filtered down south slowly while many other mid-west states have had Mobil Dc on closeout for going on a year or so now!)
I started this topic after looking for weeks on this forum. This forum has so much good information. The problem for me is that all of this information overload has caused me to question my lifetime commitment to using Castrol GTX in everything that I have ever owned. Now since I have a new Honda that requires 5W20 oil I question it more. Stumbling on GM specifications list that did not include GTX, looking at used oil analysis, and reading what others have to say about oils they use has me thinking of changing brands, types(synthetic or conventional) or both. I have never had issues with GTX but I want the best for my CR-V. I still have the factory fill and 4000 miles on it. OCI will be 5,000 miles. So far, I am considering Motorcraft blend, Pennzoil yellow, Pennzoil Plat. and Mobil Clean 5000. I got about 1000 miles left before I need to decide on one. HELP!!!
For your Honda, I would recommend the Mobil 5000 for sure! Better yet, if you absolutely must switch to 'some kind of synthetic', go with the Mobil Drive Clean 7500!! You won't be disappointed either way and your Honda will love you for using the same or very similar oil to break-in oil!
(I believe both of these oils can be had at closeout prices these days..yes, the pricing has even filtered down south slowly while many other mid-west states have had Mobil Dc on closeout for going on a year or so now!)
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