I have been told by two experts now that Ford recommends 5W-20 for better emmissions ratings on the 03's. 5W-30 is actually better for the car. Any thoughts?
5W-20 vs. 5W-30
- Thread starter Hammer
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5W-30 is better protection. Search "MOBIL 1" or hit svt forum at www.stangnet.com and check out 03'COBRA's posts on this topic.
I was worried to put "other-than-specified" lube in my 03 Cobra but not anymore, that guy knows his oil.
MOBIL 1 5W-30 in ti as of today, 1708 miles, and henceforth as well.
I was worried to put "other-than-specified" lube in my 03 Cobra but not anymore, that guy knows his oil.
MOBIL 1 5W-30 in ti as of today, 1708 miles, and henceforth as well.
There have been a lot of people that talk about this... remeber the days of straight 30 weight motor oil?
What I know from experience is this... The lower number is important... actually more important than the higher number...
5-30 sounds like a winner to me...
Also I have always liked redline products for the Porsche, but Ford has said not to use an all syn oil for some reason.
What I know from experience is this... The lower number is important... actually more important than the higher number...
5-30 sounds like a winner to me...
Also I have always liked redline products for the Porsche, but Ford has said not to use an all syn oil for some reason.
The first number is the cold viscosity and the second is the hot viscosity and the w stands for winter, not weight which most people confuse. In my experience if you drive in hot weather the running straight weight is fine you only really need 5W-30 if you live in cold climates. I am personnally going to run exactly what Ford says for the first 6-9,000 miles then might change to Mobile 1 10W-30 or equivalent depending on how everybody is experiencing at that time. You really don't want a large variance between the first and second number as this usually indicates a higher chance that the oil will break down.
Thanks for the vote of confidence, but...
My posts on lubrication on stangnet are "Cobra'03".
BTW, I was a tribologist (lubrication scientist) for 10 years with a MB in mech engineering before getting an EE degree and going into computers - keeps my hands clean. Well, most of the time. I also have a Vette restoration business (sorry) and raced in the SCCA, so I have seen it from the theory and practicality end.
Here are some of relevant topics, but I go much deeper on Stangent, and cannot be re-posting everytime someone pops up without a search first:
Some say 5w20 is because of "tighter tolerances" - I say baloney. New M5's were orginally spec'd for 10w60 Castrol synoil (not Syntec) - were they loose?
A hot engine using 20 weight mineral oil with a few miles on it will simply not have the protection of a 30 weight synoil, and there will be boundary (metal to metal) contact at the high stress points, such as cam lobes. Maybe this will not be a problem in 3years/36k miles, but somewhere down the road...well you are smart guys.
"According to Mike Riley, product design engineer with Ford Motor Company, 'Moving to 5w20 was driven by using best technology oils, CAFE requirements and customer needs'. The company believes the switch to lighter viscosity 5w20 oils will reduce carbon dioxide emissions by 190,000 metric tons a year and reduce US fuel consumption by over 21,000,000 gallons a year."
The Cobra is certfied by the EPA for its emissions and fuel mileage with mineral, 5w20. They have to continue to recommend that - you can choose to disregard. Want your eyes opened? Read this:
http://www.epa.gov/otaq/cert/dearmfr/ccd0112.pdf
0w30 Amsoil or Mobil 1 have the low temp fluidity of a 5w20, a lower pour point, and much better film strength and shear stability. Unless you drive in the Arctic, 5w30 is fine also. Since I never drive in zero weather with my Cobra, 10w30 will actually offer even higher shear stability ratings. But I will likely go with Amsoil 0w30 because I think its additives, esp the amount of phosphorous and ZDP, is better from an anti-wear standpoint. The car mfrs. pressured the oil companies to lower both AW components in order to assure 100k emissions component life - I would much rather replace my catalytic converter (with an hi-flow type no less) than an engine - how about you?
My posts on lubrication on stangnet are "Cobra'03".
BTW, I was a tribologist (lubrication scientist) for 10 years with a MB in mech engineering before getting an EE degree and going into computers - keeps my hands clean. Well, most of the time. I also have a Vette restoration business (sorry) and raced in the SCCA, so I have seen it from the theory and practicality end.
Here are some of relevant topics, but I go much deeper on Stangent, and cannot be re-posting everytime someone pops up without a search first:
Some say 5w20 is because of "tighter tolerances" - I say baloney. New M5's were orginally spec'd for 10w60 Castrol synoil (not Syntec) - were they loose?
A hot engine using 20 weight mineral oil with a few miles on it will simply not have the protection of a 30 weight synoil, and there will be boundary (metal to metal) contact at the high stress points, such as cam lobes. Maybe this will not be a problem in 3years/36k miles, but somewhere down the road...well you are smart guys.
"According to Mike Riley, product design engineer with Ford Motor Company, 'Moving to 5w20 was driven by using best technology oils, CAFE requirements and customer needs'. The company believes the switch to lighter viscosity 5w20 oils will reduce carbon dioxide emissions by 190,000 metric tons a year and reduce US fuel consumption by over 21,000,000 gallons a year."
The Cobra is certfied by the EPA for its emissions and fuel mileage with mineral, 5w20. They have to continue to recommend that - you can choose to disregard. Want your eyes opened? Read this:
http://www.epa.gov/otaq/cert/dearmfr/ccd0112.pdf
0w30 Amsoil or Mobil 1 have the low temp fluidity of a 5w20, a lower pour point, and much better film strength and shear stability. Unless you drive in the Arctic, 5w30 is fine also. Since I never drive in zero weather with my Cobra, 10w30 will actually offer even higher shear stability ratings. But I will likely go with Amsoil 0w30 because I think its additives, esp the amount of phosphorous and ZDP, is better from an anti-wear standpoint. The car mfrs. pressured the oil companies to lower both AW components in order to assure 100k emissions component life - I would much rather replace my catalytic converter (with an hi-flow type no less) than an engine - how about you?
Sorry to botch your handle like that. This is the guy I was talking about, knows waaaaay to much about oil.:thumbsup:
Thank you again for your excellent posts.
These oil posts should be in an "03 FAQ"
Thank you again for your excellent posts.
These oil posts should be in an "03 FAQ"
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