My daughter had a Honda that was spec'd for 0w-20. Her husband put 10w-40 into everything. I told him it wasn't a good idea. The Honda became an oil burner far before it's time.
Can too thick of oil be damaging?
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Kestas
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I once put 20W-50 in my 1998 Ford ZX2. It immediately caused the engine to run rough and set a code indicating a variable cam timing problem. The oil was too thick for the VCT solenoid. I switched back to 5W-30 and everything was okay after that.
wemay
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Originally Posted by buster
Engines can run on multiple viscosities but there are extremes at both ends of the spectrum you should avoid.
THIS^
Engines can run on multiple viscosities but there are extremes at both ends of the spectrum you should avoid.
THIS^
Yes and No.
In South America it's common for people to run 20w-50 in engines that spec 30 grades in the US, and these engines usually live to just as high mileages as the ones that run on 30 grades.
If you live somewhere cold ofcourse starting the engine in below freezing temps with an oil that is far too thick may damage your engine.
However in most cases say you run an engine spec'd for 5W-30 on 10W-40 it won't hurt it, or an engine specified for 10W-40 on 20W-50.
In South America it's common for people to run 20w-50 in engines that spec 30 grades in the US, and these engines usually live to just as high mileages as the ones that run on 30 grades.
If you live somewhere cold ofcourse starting the engine in below freezing temps with an oil that is far too thick may damage your engine.
However in most cases say you run an engine spec'd for 5W-30 on 10W-40 it won't hurt it, or an engine specified for 10W-40 on 20W-50.
I come from the industrial hydraulics world where oil is everything. All of the major manufacturers recommend, with some rounding errors, that the oil, AT OPERATING TEMPERATURE, be between 16cSt and 36cSt. Additive packages are important, but we expect properly designed equipment to last well over 100,000 hours, 200,000 is not unusual at all. I've many customers who maintain oil temperatures below 60C (140F), keep it clean and dry, and don't even consider replacement until 50,000 hours.
It's the dilution and water that cause most of the problems in internal combustion engines with short cycling and temperature cycling.
My SINCERE kudos to automotive power plant engineers and lubrication engineers for the amazing work they have been able to do.
All to try to have 16cSt-36cSt from below 0F to above 240F, or as near as possible at an affordable price with a reasonable lubricant.
It's the dilution and water that cause most of the problems in internal combustion engines with short cycling and temperature cycling.
My SINCERE kudos to automotive power plant engineers and lubrication engineers for the amazing work they have been able to do.
All to try to have 16cSt-36cSt from below 0F to above 240F, or as near as possible at an affordable price with a reasonable lubricant.
Your engineers know best. They wouldn't spec a 20wt if they wanted you to run a 50wt. Now there is some debate about stepping up a grade to a 30wt. For this I would tell you to do a couple UOA's on each to see how it affects things like your bearings. If there is no change or it trends downward then you are all good.
I ran 5w20 in my Journey which is what it called for. This engine called for 5w30 in generations before it. In the 100,000km (60K miles) I owned it before it was totaled I saw nothing but superb UOA's using the 5w20. 0ppm for all wear metals, 4ppm on the Iron after a 9K run. TBN of 6.8 and Tan in the mid 1's. This UOA is posted here on BITOG under my username in the last year if you want to see it.
Happy motoring.
I ran 5w20 in my Journey which is what it called for. This engine called for 5w30 in generations before it. In the 100,000km (60K miles) I owned it before it was totaled I saw nothing but superb UOA's using the 5w20. 0ppm for all wear metals, 4ppm on the Iron after a 9K run. TBN of 6.8 and Tan in the mid 1's. This UOA is posted here on BITOG under my username in the last year if you want to see it.
Happy motoring.
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Originally Posted by StevieC
Your engineers know best. They wouldn't spec a 20wt if they wanted you to run a 50wt. Now there is some debate about stepping up a grade to a 30wt. For this I would tell you to do a couple UOA's on each to see how it affects things like your bearings. If there is no change or it trends downward then you are all good.
I ran 5w20 in my Journey which is what it called for. This engine called for 5w30 in generations before it. In the 100,000km (60K miles) I owned it before it was totaled I saw nothing but superb UOA's using the 5w20. 0ppm for all wear metals, 4ppm on the Iron after a 9K run. TBN of 6.8 and Tan in the mid 1's. This UOA is posted here on BITOG under my username in the last year if you want to see it.
Happy motoring.
Did the fuel mileage get better?
I've been contemplating moving down from 10W-60 to, say 0W-40 on my BMW.
Your engineers know best. They wouldn't spec a 20wt if they wanted you to run a 50wt. Now there is some debate about stepping up a grade to a 30wt. For this I would tell you to do a couple UOA's on each to see how it affects things like your bearings. If there is no change or it trends downward then you are all good.
I ran 5w20 in my Journey which is what it called for. This engine called for 5w30 in generations before it. In the 100,000km (60K miles) I owned it before it was totaled I saw nothing but superb UOA's using the 5w20. 0ppm for all wear metals, 4ppm on the Iron after a 9K run. TBN of 6.8 and Tan in the mid 1's. This UOA is posted here on BITOG under my username in the last year if you want to see it.
Happy motoring.
Did the fuel mileage get better?
I've been contemplating moving down from 10W-60 to, say 0W-40 on my BMW.
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I ran what the manual tells me so I have no comparison. I was just stating that the 2.4L in my Journey called for 5w30 in years past and in mine it called for 5w20 so I know it would be fine with a 5w30 but I ran 5w20 instead.
You will get marginal economy gains with a 20wt versus a 30wt.
You will get marginal economy gains with a 20wt versus a 30wt.
Originally Posted by StevieC
Your engineers know best. They wouldn't spec a 20wt if they wanted you to run a 50wt. Now there is some debate about stepping up a grade to a 30wt. For this I would tell you to do a couple UOA's on each to see how it affects things like your bearings. If there is no change or it trends downward then you are all good.
I ran 5w20 in my Journey which is what it called for. This engine called for 5w30 in generations before it. In the 100,000km (60K miles) I owned it before it was totaled I saw nothing but superb UOA's using the 5w20. 0ppm for all wear metals, 4ppm on the Iron after a 9K run. TBN of 6.8 and Tan in the mid 1's. This UOA is posted here on BITOG under my username in the last year if you want to see it.
Happy motoring.
Which engineers are you talking about? Are you saying that seemingly identical engines sold in different countries were independently designed?
Your engineers know best. They wouldn't spec a 20wt if they wanted you to run a 50wt. Now there is some debate about stepping up a grade to a 30wt. For this I would tell you to do a couple UOA's on each to see how it affects things like your bearings. If there is no change or it trends downward then you are all good.
I ran 5w20 in my Journey which is what it called for. This engine called for 5w30 in generations before it. In the 100,000km (60K miles) I owned it before it was totaled I saw nothing but superb UOA's using the 5w20. 0ppm for all wear metals, 4ppm on the Iron after a 9K run. TBN of 6.8 and Tan in the mid 1's. This UOA is posted here on BITOG under my username in the last year if you want to see it.
Happy motoring.
Which engineers are you talking about? Are you saying that seemingly identical engines sold in different countries were independently designed?
The engineers that designed the engine. If they call for two different weight oils in two different countries than either can be used if the ambient temperature is suitable.
Lets say at 5000 rpm, a 10w-30 is at 60 psi and a 20w-50 is at 80 psi. Would that excess pressure have any impact on hydraulic lifters?
Also, is aeration a higher concern with thicker oil?
Also, is aeration a higher concern with thicker oil?
OVERKILL
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Originally Posted by RDY4WAR
Lets say at 5000 rpm, a 10w-30 is at 60 psi and a 20w-50 is at 80 psi. Would that excess pressure have any impact on hydraulic lifters?
Also, is aeration a higher concern with thicker oil?
No and no.
Lets say at 5000 rpm, a 10w-30 is at 60 psi and a 20w-50 is at 80 psi. Would that excess pressure have any impact on hydraulic lifters?
Also, is aeration a higher concern with thicker oil?
No and no.
Nick1994
$100 site donor 2024
Here's the owner's manual for my Sonata in the UK and Australia. Allows for up to 20w50.
Here in the U.S. it says 5w20, 5w30, and 10w30.
https://carmanuals2.com/d/92949
Here in the U.S. it says 5w20, 5w30, and 10w30.
https://carmanuals2.com/d/92949
Originally Posted by Nick1994
Here's the owner's manual for my Sonata in the UK and Australia. Allows for up to 20w50.
Here in the U.S. it says 5w20, 5w30, and 10w30.
https://carmanuals2.com/d/92949
Looks like a similar chart for the Elantra. In the U.S., it's 5W-20, 5W-30 and 10W-30. However, in the UK and Australia it allows up to 20W-50. Elantra manual
*Edit: Also interesting, the OCI spelled out in the U.S. manual is 7500 miles, 3750 miles in severe usage. In the RHD manual (UK and Australia), the OCI is 15,000km (9,320 miles) and 7500km (4,660 miles) in severe usage.
Here's the owner's manual for my Sonata in the UK and Australia. Allows for up to 20w50.
Here in the U.S. it says 5w20, 5w30, and 10w30.
https://carmanuals2.com/d/92949
Looks like a similar chart for the Elantra. In the U.S., it's 5W-20, 5W-30 and 10W-30. However, in the UK and Australia it allows up to 20W-50. Elantra manual
*Edit: Also interesting, the OCI spelled out in the U.S. manual is 7500 miles, 3750 miles in severe usage. In the RHD manual (UK and Australia), the OCI is 15,000km (9,320 miles) and 7500km (4,660 miles) in severe usage.
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Yep, they allow for up to 20w50.
Some people in this board think that pouring 20w50 in your engine is about as good as pouring sand into it.
Some people in this board think that pouring 20w50 in your engine is about as good as pouring sand into it.
It may allow 20w50 but it might not be optimal for bearings. The reason they "allow" it is because there might be limited choices in certain parts of the world and the trade off could be minor wear/tear that results in using a less optimal thickness of oil. I'm talking 5w30 to 20w50 sort of scenario.
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Can excessive viscosity accelerate bearing wear due to increased shear and heat?
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Originally Posted by StevieC
It may allow 20w50 but it might not be optimal for bearings. The reason they "allow" it is because there might be limited choices in certain parts of the world and the trade off could be minor wear/tear that results in using a less optimal thickness of oil. I'm talking 5w30 to 20w50 sort of scenario.
Your engineers know best. They wouldn't spec a 50wt if they only wanted you to run a 20wt.
It may allow 20w50 but it might not be optimal for bearings. The reason they "allow" it is because there might be limited choices in certain parts of the world and the trade off could be minor wear/tear that results in using a less optimal thickness of oil. I'm talking 5w30 to 20w50 sort of scenario.
Your engineers know best. They wouldn't spec a 50wt if they only wanted you to run a 20wt.
They "Allow" a 50wt not "Spec" a 50wt. There is a difference in what I said.
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