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Old 02-17-2008, 09:42 AM   #1
owlface
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Default put the wrong oil in my car, is this bad?

I have a 99 Camry with 125,xxx miles, and it runs great. I just changed my oil and I accidentally put in 5w20 instead of 5w30. Is this a huge problem? Will this cause premature wear on engine parts?
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Old 02-17-2008, 10:11 AM   #2
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Default put the wrong oil in my car, is this bad?

Shouldn't be a problem for winter. Make sure to change it back to the recommended weight before warm weather gets here. With oil, as the numbers get larger, the oil viscosity gets thicker..... Multi-weight like 5W-20 is fine for winter, and 5w-30 or 10w-40 is better for warmer months.
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Old 02-17-2008, 11:28 AM   #3
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Default put the wrong oil in my car, is this bad?

I think it will be ok for one round. My engine requires 5-20W all year.
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Old 02-17-2008, 12:06 PM   #4
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Default put the wrong oil in my car, is this bad?

Double-check the manual. Most cars will allow several different viscosities within certain temperature ranges. Just make sure that you stay within the recommended temperatures for that oil.

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Old 02-17-2008, 12:21 PM   #5
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Default put the wrong oil in my car, is this bad?

thank you sir
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Old 02-17-2008, 02:05 PM   #6
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Default put the wrong oil in my car, is this bad?

The only reason Ford and Honda went to 5w20 is for increased fuel economy. Most makers of 5w20 oil have a warning that says " Only use 5w20 if it's recommended by your cars manufacturer " or similar. The only way you would ever get me to use 5w20 even when recommended my the manufacturer would be if it was synthetic oil. 5w20 will have a very hard time protecting an engine under high load high temp conditions. Screw the 1/2 mile to the gallon more you might get out of it.

Now your problem. If you used conventional 5w20 if would get rid of it before doing any extended high speed driving or the ambient temps get much over 50-60 degree's F. Which ever comes first. If you used synthetic oil just run it until your next change is do unless where you live has extreme ambient temps in the summer if so dump it before hand.
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Old 02-17-2008, 02:46 PM   #7
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Default put the wrong oil in my car, is this bad?

i always just use 10w40 in all my cars and motorcycles. never really bothered getting the exact one they specify. seems to be fine. i live in CA though, so it doesn't get too cold.
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Old 02-17-2008, 02:46 PM   #8
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Default put the wrong oil in my car, is this bad?

I have full synthetic (tho not really synthetic now (mobil1 5w20 full synthetic)) and it runs fine in summer/winter. Just dont switch to synthetic if you have put in non-synthetic motor oil in the past, especially with a camry with that many miles. You will cause problems and have oil leaks/burning oil
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Old 02-17-2008, 04:37 PM   #9
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Default put the wrong oil in my car, is this bad?

Don't push the car (careful with the gas and don't tow or carry heavy loads) and change it before the weather gets too warm. You will be fine.
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Old 02-17-2008, 07:53 PM   #10
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Default put the wrong oil in my car, is this bad?

The truth is that most 5W-20's are in the upper cSt range of the 20W scale, and that most 5W-30's are in the lower cSt portion of the 30W scale - this is when @100C.

Then, you've got 5W-30's shearing down into upper 20W range anyways, and 20W's being a better "built" oil that don't shear down as much.

So basically, unless you're tracking your ride and beating the ever living sh1t out of it, you'll be fine.

The reason Ford and Honda went to 20W's instead of 30W's was not only that it saves on gas...it's that 20W's are going to reduce startup wear (where most wear occurs) and that oil technology had finally progressed to the point that dino (read: cheaper oils not having to be synthetic) oil had finally reached the point where 20W would be viable for protection.

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Old 02-17-2008, 09:02 PM   #11
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Default put the wrong oil in my car, is this bad?

I thought that the lower number is the viscosity when the oil and engine are cold, and the higher number is when the engine reaches operating temperature. http://auto.howstuffworks.com/question164.htm

If this is the case, then the oil would be too thin when your car warms up to operating temperature.
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Old 02-17-2008, 09:08 PM   #12
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Default put the wrong oil in my car, is this bad?

Quote:
Originally posted by: CptCrunch
I have full synthetic (tho not really synthetic now (mobil1 5w20 full synthetic)) and it runs fine in summer/winter. Just dont switch to synthetic if you have put in non-synthetic motor oil in the past, especially with a camry with that many miles. You will cause problems and have oil leaks/burning oil
Bull. Pure and simple.

You can switch over to synthetic at any point and a properly maintained engine will NOT have problems with leaks or burning oil. If you experience issues with leaking or burning oil after switching to synthetic on an older car, those problems were pre-existing damage that is simply made evident by the synthetic oil. Synthetic absolutely, positively does not cause those problems. Period.

I switched my 914 over to synthetic with 120,000 miles on the car and 26 years on the engine. Oil consumption went down and there were zero new leaks.

I switched over on my 944 at about 145,000 miles. Still no consumption nor leaks.

I switched the Volvo to synthetic at 118,000 miles. Again, no consumption, no leaks.

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Old 02-17-2008, 11:17 PM   #13
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Default put the wrong oil in my car, is this bad?

Quote:
Originally posted by: chucky2
The truth is that most 5W-20's are in the upper cSt range of the 20W scale, and that most 5W-30's are in the lower cSt portion of the 30W scale - this is when @100C.

Then, you've got 5W-30's shearing down into upper 20W range anyways, and 20W's being a better "built" oil that don't shear down as much.

Chuck
Winnar! There's very little difference in the real weight of 20w vs 30w oils on the market today.
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Old 02-18-2008, 12:38 AM   #14
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Default put the wrong oil in my car, is this bad?

Quote:
Originally posted by: cprince
I thought that the lower number is the viscosity when the oil and engine are cold, and the higher number is when the engine reaches operating temperature. http://auto.howstuffworks.com/question164.htm

If this is the case, then the oil would be too thin when your car warms up to operating temperature.
The lower number (the 5 in a 5W-yy lets say) basically represents the pumpability and flow charactaristics of that oil in meeting the 5W spec. It's just not cSt at 40C or 30C or whatever spec the xW you're going for, there are pumpability specs those oils have to meet to be able to put that 0W or 5W or 10W in front of the -yy number.

The -yy number in a xW-yy is what viscosity that oil is at (usually measured in centistokes, or cSt) at 100C. So the upper range of the 20W @ 100C scale in cSt is 9.something...the lower range of a 30W @ 100C is 9.something. So what you have are most xW-20's being at the upper end of the 20W cSt @ 100C scale, and most 0W, 5W, and 10W-30's being at the lower range of the 30W cSt @ 100C scale.

Because of the requirements Ford and Honda have for the xW-20's in their testing, those oils have to be "built" better than the 30W's. This normally results in less shear. So after say 1500 miles, that 20W will be close to it's starting cSt @100C number, while a 5W-30 after 1500 miles will most likely have sheared into the high 20W cSt @ 100C range.

Again, if you are not experiencing high fuel dilute, aren't running your engine at the ragged edge for sustained periods, or don't have a mechanical condition that would warrant a higher viscosity and/or higher HT/HS oil, then running a xW-20 vs. a 5W-30 - especially in the winter - basically will mean nothing.

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Old 02-18-2008, 01:02 AM   #15
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Default put the wrong oil in my car, is this bad?

Quote:
Originally posted by: chucky2
The truth is that most 5W-20's are in the upper cSt range of the 20W scale, and that most 5W-30's are in the lower cSt portion of the 30W scale - this is when @100C.

Then, you've got 5W-30's shearing down into upper 20W range anyways, and 20W's being a better "built" oil that don't shear down as much.

So basically, unless you're tracking your ride and beating the ever living sh1t out of it, you'll be fine.

The reason Ford and Honda went to 20W's instead of 30W's was not only that it saves on gas...it's that 20W's are going to reduce startup wear (where most wear occurs) and that oil technology had finally progressed to the point that dino (read: cheaper oils not having to be synthetic) oil had finally reached the point where 20W would be viable for protection.

Chuck
I see your point but why do most if not all oil companies state "SAE 5W-20 should only be used in vehicles where SAE 5W-20 is recommended by manufacturer."
The reason is, the oil companies do not want to be responsible for any possible damage done. If the manufacture specifies 5w20 oil the oil company is not liable as long as their oil meets specs.

The auto manufacturers can claim tighter clearances make up for 5w20 but its a line of bull. They are just doing everything they can to meet CAFE standards.

Yup most engine wear happens on startup. Thats one of the reasons conventional oil is crap. Synthetic is the only way to go. Better hot and cold and they keep engines much cleaner.

On some statements made other posters. I would never use 10w40 in any modern car unless it was called for by the manufacture. Conventional multiviscosity oil's are made by taking a lighter oil and adding viscosity index improver's to make the oil perform as a thicker base oil would at high temperature. So a 5w30 oil is really a SAE 5w oil with viscosity index improver's added to make it perform like a SAE 30 oil at 100C. 10w40 is too far of a stretch. This is because you need to add to much viscosity index improver to get the 40 rating. So get rid of the 10w40. Any car made in the last 30 years should be just fine using 10w30 in hot climates and 5w30 in cold climates. If under extreme heat or load go to a 15w40 or synthetic oil.

You can switch an engine to synthetic oil anytime. The sooner the better.
Keep in mind, if you only keep a car for 3 or 4 years it would not be worth it
unless you live in a extreme climate. People that keep cars for as long as possible are the ones that should be using synthetic oil. I started using Mobil 1 in the early 80's and have used it in every 4cycle engine I have owned since. I have only owned 2 new cars the rest had 100k miles or more when I got them. I have never had oil leaks occur after switching to synthetic oil. I have never had a engine fail or use oil ever. Knock on wood. I live in Mn and use 0w30 or 5w30 Mobil 1 in the winter and 5w30 or 10w30 Mobil 1 in the summer.








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Old 02-18-2008, 01:33 AM   #16
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Default put the wrong oil in my car, is this bad?

Quote:
Originally posted by: wonderwrench

I see your point but why do most if not all oil companies state "SAE 5W-20 should only be used in vehicles where SAE 5W-20 is recommended by manufacturer."
The reason is, the oil companies do not want to be responsible for any possible damage done. If the manufacture specifies 5w20 oil the oil company is not liable as long as their oil meets specs.
The oil companies do this because they don't themselves want to be held liable for any damage. Oil companies aren't doing millions of miles of engine testing on all the engines spec'd for 30W, so no way are they going to sign up for any wiggle room when it comes to millions of users maybe installing 20W oils in their 30W spec'd engines...then something happens and it would have to be the oil right? Whamo...lawsuits galore. All they have to do to prevent this is spend .002c on printed text on their bottles and documentation with that line and they're covered. Wouldn't you?

Quote:
The auto manufacturers can claim tighter clearances make up for 5w20 but its a line of bull. They are just doing everything they can to meet CAFE standards.
It's both. Modern engines have tighter clearances, tolerances, and much better manufacturing deviation numbers. But safely using 20W's could not be possible without modern oil technology. Honda doesn't need to go to xW-20's to meet CAFE standards and isn't about to take a dent in their standing as most reliable auto manufacturer...they don't need to run to xW-20 oils just because Ford did. Honda staying on xW-30's and they'd still win against Ford on mileage and longevity...so why'd Honda switch then? Couldn't it have been they felt it was time since oil tech. had finally reached that point?

Quote:
Yup most engine wear happens on startup. Thats one of the reasons conventional oil is crap. Synthetic is the only way to go. Better hot and cold and they keep engines much cleaner.
I don't argue that synthetic is better than dino on an apples to apples basis, however there are 10's of Millions of engines that have had dino their whole life and go well into the 100k mi. range. You're making it sound like modern dino's are cr@p here and that's far far from the truth. And Yes, I do use synthetics so I'm not a synthetic h8t3r...

Quote:
On some statements made other posters. I would never use 10w40 in any modern car unless it was called for by the manufacture. Conventional multiviscosity oil's are made by taking a lighter oil and adding viscosity index improver's to make the oil perform as a thicker base oil would at high temperature. So a 5w30 oil is really a SAE 5w oil with viscosity index improver's added to make it perform like a SAE 30 oil at 100C. 10w40 is too far of a stretch. This is because you need to add to much viscosity index improver to get the 40 rating. So get rid of the 10w40. Any car made in the last 30 years should be just fine using 10w30 in hot climates and 5w30 in cold climates. If under extreme heat or load go to a 15w40 or synthetic oil.
I don't know if I'd go so far as to state that a 5W-30 is a 5W basestock with VII added to achieve 30W cSt @ 100C performance. Don't forget on modern dino's they add PAO, ester, PAO/ester and/or Pour Point Depressants (PPD's) to aid in cold flow characteristics. That 5W-30 may be more like 80% 20W, 19% 30W (up in the middle maybe of the cSt @ 100C scale), and then VII and PPD mixed in to get you your final 5W and 30W @ 100C specs. There are tons of combinations here, and the oil blenders (whoever that may be) formalate what we all get to use based on price, performance, and availability of stocks and adds...all to meet whatever price and performance is desired for each of the particular oils they're selling. For the vast majority of users when using modern dino API SM spec oils in modern engines, there is no right or wrong to that approach - even the cheapest API SM spec oils are going to get people there to 100k as long as they change on schedule and have a properly operating engine.

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Old 02-18-2008, 08:55 AM   #17
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Default put the wrong oil in my car, is this bad?

Quote:
Originally posted by: wonderwrench
The only reason Ford and Honda went to 5w20 is for increased fuel economy. Most makers of 5w20 oil have a warning that says " Only use 5w20 if it's recommended by your cars manufacturer " or similar.
Also has to do with the increased complexities of valve trains with hydraulic lifters, variable valve train tappets, increase manufacturing precisions and closer tolerances, etc. The thinner oil can reach these areas better, particularly when the engine is cold.

SVT engineers recommend 5W-20 on the Cobras for example because of the tight hand built clearances of engine components.
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Old 02-18-2008, 02:00 PM   #18
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Default put the wrong oil in my car, is this bad?

5W-20 is not any thinner than 5W-30 when it's cold, though.
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Old 02-18-2008, 02:35 PM   #19
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Default put the wrong oil in my car, is this bad?

Quote:
Originally posted by: LTC8K6
5W-20 is not any thinner than 5W-30 when it's cold, though.
Yep, they sure are. I picked Pennzoil lineup as an example, but they're all mostly going to be the same:

Pennzoil Platinum Product Data Sheet

Pennzoil Dino Product Data Sheet

Pennzoil SUV, Truck, and Minivan Product Data Sheet

Pay attention to the cSt @ 40C (and cSt @ 100C if you want to compare at temp viscosities), MRV, and CCS values between the 20W's and 30W's.

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Old 02-18-2008, 03:03 PM   #20
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Default put the wrong oil in my car, is this bad?

Quote:
Originally posted by: exdeath
Quote:
Originally posted by: wonderwrench
The only reason Ford and Honda went to 5w20 is for increased fuel economy. Most makers of 5w20 oil have a warning that says " Only use 5w20 if it's recommended by your cars manufacturer " or similar.
Also has to do with the increased complexities of valve trains with hydraulic lifters, variable valve train tappets, increase manufacturing precisions and closer tolerances, etc. The thinner oil can reach these areas better, particularly when the engine is cold.

SVT engineers recommend 5W-20 on the Cobras for example because of the tight hand built clearances of engine components.
Thats what the manufactures say, its still BS. They use 5w20 to increase fuel economy and 5w20 oil specs called for less burn off than previous oil specs required. So 5w20 helped achieve lower emissions. Read this http://www.epa.gov/otaq/cert/dearmfr/ccd0112.pdf
Sure is strange that the EPA would be so tight on the use of 5w20 if the manufacturers were only using 5w20 because they tightened clearances and for better startup lubrication. 5w20 and 5w30 should have the same viscosity cold so this is a moot point.

Today many oils that are not 5w20 meet the ILSAC GF-3 spec so they have no more burn off than 5w20 oil. So using 5w20 only really increases fuel economy and only marginally at best. 5w20 will increase engine wear at high engine loads and or high temperatures. Oil can only be so thin before metal to metal contact occurs. Also keep in mind over the last several oil spec changes they have all but eliminated the use of Phosphorus and zinc which were the best extreme pressure lubricants available.

Most if not all conventional oils today are not capable of protecting engines under extreme conditions because of the lack of Phosphorus and zinc. 5w20 just will not cut it sorry, the oil film is just to thin at high temps. And do not say people do not drive under extreme conditions as very few do not. Idling in traffic with the ac on when its 90+ degrees . Pulling a trailer when its 90+. Driving at high speed over long distances when its 90+.

The days were engines last near forever if taken care of are over. Synthetic oil's ability to stay in acceptable viscosity range under extreme temps will help but Phosphorus and zinc will affect them also.

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Old 02-20-2008, 02:23 PM   #21
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Default put the wrong oil in my car, is this bad?

Quote:
Originally posted by: wonderwrench
Quote:
Originally posted by: exdeath
Quote:
Originally posted by: wonderwrench
The only reason Ford and Honda went to 5w20 is for increased fuel economy. Most makers of 5w20 oil have a warning that says " Only use 5w20 if it's recommended by your cars manufacturer " or similar.
Also has to do with the increased complexities of valve trains with hydraulic lifters, variable valve train tappets, increase manufacturing precisions and closer tolerances, etc. The thinner oil can reach these areas better, particularly when the engine is cold.

SVT engineers recommend 5W-20 on the Cobras for example because of the tight hand built clearances of engine components.
Thats what the manufactures say, its still BS. They use 5w20 to increase fuel economy and 5w20 oil specs called for less burn off than previous oil specs required. So 5w20 helped achieve lower emissions. Read this http://www.epa.gov/otaq/cert/dearmfr/ccd0112.pdf
Sure is strange that the EPA would be so tight on the use of 5w20 if the manufacturers were only using 5w20 because they tightened clearances and for better startup lubrication. 5w20 and 5w30 should have the same viscosity cold so this is a moot point.

Today many oils that are not 5w20 meet the ILSAC GF-3 spec so they have no more burn off than 5w20 oil. So using 5w20 only really increases fuel economy and only marginally at best. 5w20 will increase engine wear at high engine loads and or high temperatures. Oil can only be so thin before metal to metal contact occurs. Also keep in mind over the last several oil spec changes they have all but eliminated the use of Phosphorus and zinc which were the best extreme pressure lubricants available.

Most if not all conventional oils today are not capable of protecting engines under extreme conditions because of the lack of Phosphorus and zinc. 5w20 just will not cut it sorry, the oil film is just to thin at high temps. And do not say people do not drive under extreme conditions as very few do not. Idling in traffic with the ac on when its 90+ degrees . Pulling a trailer when its 90+. Driving at high speed over long distances when its 90+.

The days were engines last near forever if taken care of are over. Synthetic oil's ability to stay in acceptable viscosity range under extreme temps will help but Phosphorus and zinc will affect them also.
You have an engineering degree?

Also what is the piston to wall clearance of the 2003 Cobra 4v SC engine? Look it up. The engines are built by hand and the engineers who designed and built them say 5W20 and they are a bunch of gear heads who crave power and couldn't care less about 1 MPG. The design was validated on a dyno alternating between max power and max torque for something like 400 hours non stop. That's more extreme than anything you're thinking of.

I hardly think 5W20 was chosen to increase fuel economy by .5 mpg on a car that's only rated 16 MPG in the first place... I just don't think MPG was a priority. Tight clearances may help in efficiency and in meeting CAFE standards (*puke*) thus indirectly linking 5W20 to the cause and effect result of higher fuel economy. But 5W20 is merely a necessitated byproduct to the tighter clearances that are more responsible for the efficiency gains than the oil itself.

It's a bit of a misnomer and logical fallacy:

1) engine built tighter to improve efficiency and mileage
2) thinner oil required for the tighter components
3) therefor thinner oil was chosen for better mileage

I wonder what is worse, going with a lighter oil that flows better at the expense of decreased lubrication or no lubrication at all when you hammer the throttle and oil pressure spikes and the thicker oil doesn't flow as well momentarily in a tight engine.
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Old 02-20-2008, 03:18 PM   #22
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"Pay attention to the cSt @ 40C (and cSt @ 100C if you want to compare at temp viscosities)"

I understand, but for all intents and purposes, 5W-20 and 5W-30 are similar oils when they are cold. They flow the same in cold weather. The average joe doesn't need to get into centistokes.
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Old 02-20-2008, 10:23 PM   #23
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Quote:
Originally posted by: exdeath
Quote:
Originally posted by: wonderwrench
Quote:
Originally posted by: exdeath
Quote:
Originally posted by: wonderwrench
The only reason Ford and Honda went to 5w20 is for increased fuel economy. Most makers of 5w20 oil have a warning that says " Only use 5w20 if it's recommended by your cars manufacturer " or similar.
Also has to do with the increased complexities of valve trains with hydraulic lifters, variable valve train tappets, increase manufacturing precisions and closer tolerances, etc. The thinner oil can reach these areas better, particularly when the engine is cold.

SVT engineers recommend 5W-20 on the Cobras for example because of the tight hand built clearances of engine components.
Thats what the manufactures say, its still BS. They use 5w20 to increase fuel economy and 5w20 oil specs called for less burn off than previous oil specs required. So 5w20 helped achieve lower emissions. Read this http://www.epa.gov/otaq/cert/dearmfr/ccd0112.pdf
Sure is strange that the EPA would be so tight on the use of 5w20 if the manufacturers were only using 5w20 because they tightened clearances and for better startup lubrication. 5w20 and 5w30 should have the same viscosity cold so this is a moot point.

Today many oils that are not 5w20 meet the ILSAC GF-3 spec so they have no more burn off than 5w20 oil. So using 5w20 only really increases fuel economy and only marginally at best. 5w20 will increase engine wear at high engine loads and or high temperatures. Oil can only be so thin before metal to metal contact occurs. Also keep in mind over the last several oil spec changes they have all but eliminated the use of Phosphorus and zinc which were the best extreme pressure lubricants available.

Most if not all conventional oils today are not capable of protecting engines under extreme conditions because of the lack of Phosphorus and zinc. 5w20 just will not cut it sorry, the oil film is just to thin at high temps. And do not say people do not drive under extreme conditions as very few do not. Idling in traffic with the ac on when its 90+ degrees . Pulling a trailer when its 90+. Driving at high speed over long distances when its 90+.

The days were engines last near forever if taken care of are over. Synthetic oil's ability to stay in acceptable viscosity range under extreme temps will help but Phosphorus and zinc will affect them also.
You have an engineering degree?

Also what is the piston to wall clearance of the 2003 Cobra 4v SC engine? Look it up. The engines are built by hand and the engineers who designed and built them say 5W20 and they are a bunch of gear heads who crave power and couldn't care less about 1 MPG. The design was validated on a dyno alternating between max power and max torque for something like 400 hours non stop. That's more extreme than anything you're thinking of.

I hardly think 5W20 was chosen to increase fuel economy by .5 mpg on a car that's only rated 16 MPG in the first place... I just don't think MPG was a priority. Tight clearances may help in efficiency and in meeting CAFE standards (*puke*) thus indirectly linking 5W20 to the cause and effect result of higher fuel economy. But 5W20 is merely a necessitated byproduct to the tighter clearances that are more responsible for the efficiency gains than the oil itself.

It's a bit of a misnomer and logical fallacy:

1) engine built tighter to improve efficiency and mileage
2) thinner oil required for the tighter components
3) therefor thinner oil was chosen for better mileage

I wonder what is worse, going with a lighter oil that flows better at the expense of decreased lubrication or no lubrication at all when you hammer the throttle and oil pressure spikes and the thicker oil doesn't flow as well momentarily in a tight engine.
No degree here how about you?

Looks like the spec is 0.01040-.026 mm and yup thats tight. Small block chev engines 30 years ago had piston shirts larger than the bore. The OEM pistons were chamfered at the bottom so you could get them started in the bore and you used a rubber hammer or a wooden block to drive them in so whats your point?

2003 Cobra 4v SC engines had a tendency to seize pistons under high rpm and heavy loads so I would not be bragging them up. If they make 10K they seem to run forever though. The ones that seized must have been on the tight end of spec.
If the engineers were not worried why were the skirts Teflon coated?

As far as why they used 5w20? It's possible they had to, to pass emissions testing.
If that is not the case it may have been an experiment to see if it could be done.
Its also a well known fact ford modular engines will run the oil sump dry under extended high rpm use. Road racers tried for over 2 years to eliminate bearing failure caused by this problem. They found that the sump runs dry because all the oil ends up in the top end. The only fix that worked was a dry sump and it was not legal. Ford may have found using water for oil may have been the only way they could get around this problem without using a dry sump. They could restrict oil flow to the top end but then they would have valve train problems. They could increase the size of the oil returns from the heads. The first thing racers tried and it does not get the job done. So after looking at the facts it was either done to pass emissions or to keep the sump from running dry.

I can use the 2005 Ford GT 5.4L 4V SC engine as my example. NO 5w20 here.
I wonder why they used 5W50?. This is a hand built engine. Holds 9.5 qts of oil. Has a huge oil cooler. Dry sump oil system. ??? Dry sump and 9.5 qts of oil, I don't think you could run the sump dry on this baby.

This thread has gone off topic. I'm done
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Old 02-21-2008, 11:11 AM   #24
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The pistons were made tight on purpose because the average Joe who knows nothing about cars would complain about piston slap noise with the forged pistons. So they were made tight.

Under high RPM and high loads under prolonged boost (ie: top speed runs, winding out 5th/6th gear, etc) the expansion of forged aluminum pistons and iron block with tight cylinder wall clearance, and high charge temps from a over driven inefficient Eaton roots blower, and no cooling mods, is what causes those engines to score or seize.

Don't stay in boost for 10 minutes non stop uphill in the middle of summer in 5th/6th gear and wrap the speedo around and it will be fine.

Anybody who actually knows about cars, or knows better than to just over spin the stock blower with a smaller pulley with no supporting mods knows this.

Interesting about the 5W50 on the GT, wasn't aware of that.
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Old 02-21-2008, 11:03 PM   #25
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Quote:
Originally posted by: wonderwrench

I can use the 2005 Ford GT 5.4L 4V SC engine as my example. NO 5w20 here.
I wonder why they used 5W50?. This is a hand built engine. Holds 9.5 qts of oil. Has a huge oil cooler. Dry sump oil system. ??? Dry sump and 9.5 qts of oil, I don't think you could run the sump dry on this baby.
Sounds a lot like the 5L BMW S85 engine. ~9.5 quarts of 10w60 oil. Why? Cause it's built so loose that it eats oil at upwards of 1 quart every couple thousand miles (many people have experienced even worse than that). If they used 5w30 (like on many other M engines), it would be a quart every tank or two of gas.
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Understeer is when you hit the wall with the front of the car and oversteer is when you hit the wall with the rear of the car.
Horsepower is how fast you hit the wall, torque is how far you take the wall with you.
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