Tighter tolerances is a total joke. Look. I don't care if anyone pays any attention to my comments or not. I am merely relaying info passed onto me from my many lengthy conversations with him. Use whatever you like. I am sure there is no harm using a 5w-30 however the 5w-20 spec is pure politics and CAFE. As far as tolerances ask whoever made that statement which tolerances are tighter. A motor is a motor with rings on the pistons and so on. Perhaps they are referring to the oil passages however if you really look they arent much different than a 302. And since there aren't any pushrods what tolerances are actually tighter. Look guys use whatever you want. I don't care. The 4.6 was built to rev. At 4500 rpms which oil viscosity has stronger film strength. Common sense. Aren't the new 5.0 mustangs spec a 50 weight oil.... I would think that the 5.0 4v would have tighter tolerances than the old 4.6 wouldn't they,these marvels of engineering. You tell me
50/50 Mix 5w20 & 5w30 = 5w25
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Originally Posted By: demarpaint
Originally Posted By: boxcartommie22
clevy, is that true about your uncle?miss information here could cost alot of people their engines..what about the tight clearances of the new modulars?is that a myth?
According to his uncle it seems 30 grade oil isn't good in that application either, which is interesting. From what I've read Ford tested the living [censored] out of those engines with the oil spec on the fill cap, in desert heat as well. IIRC Johnny was with the Pennzoil company during that time and he and I discussed the results at great length. He said the 20 grade oil did quite well.
Not what I wrote. I wrote that it was built for a 40 weight. And tested extensively with it. Then ford erred on the side of caution by specifying a 30 weigh. Then a few years later they back spec'ed everything with 5w-20. The ford Aussie models are all spec'ed to a 5w-30 still I believe. They use the same motors we do don't they. Why is it different there..... No CAFE laws and the aboriginals aren't complaining about air quality and blah blah blah. My uncle wayne started at ford in when he was 17 years old. Ford helped finance his education and he went from the line to r+d. He retired at 55 with a fat pension and a cottage on Georgian bay. I can only ask that you read what I wrote and apply some common sense. K. I am done for today. I probably stirred up a great big pile of poop here.
Originally Posted By: boxcartommie22
clevy, is that true about your uncle?miss information here could cost alot of people their engines..what about the tight clearances of the new modulars?is that a myth?
According to his uncle it seems 30 grade oil isn't good in that application either, which is interesting. From what I've read Ford tested the living [censored] out of those engines with the oil spec on the fill cap, in desert heat as well. IIRC Johnny was with the Pennzoil company during that time and he and I discussed the results at great length. He said the 20 grade oil did quite well.
Not what I wrote. I wrote that it was built for a 40 weight. And tested extensively with it. Then ford erred on the side of caution by specifying a 30 weigh. Then a few years later they back spec'ed everything with 5w-20. The ford Aussie models are all spec'ed to a 5w-30 still I believe. They use the same motors we do don't they. Why is it different there..... No CAFE laws and the aboriginals aren't complaining about air quality and blah blah blah. My uncle wayne started at ford in when he was 17 years old. Ford helped finance his education and he went from the line to r+d. He retired at 55 with a fat pension and a cottage on Georgian bay. I can only ask that you read what I wrote and apply some common sense. K. I am done for today. I probably stirred up a great big pile of poop here.
Originally Posted By: Clevy
I can only ask that you read what I wrote and apply some common sense. K. I am done for today.
LOL, talk about something in short supply here on BITOG...
No doubt the average owner is fine with the 5W-20... I even use it in my mom's '03 Mercury, but she's 81 and just putters around town, so the oil is seldom at full operating temp... Me, as I stated before my stuff is run hard, probably more so than 99% of the general public...
Originally Posted By: A_Harman
I do appreciate the comedic value of mixing 20-weight and 30-weight and ending up with a "25-weight", but that's just not how it works. The SAE viscosity rating system just does not allow it.
20-weight viscosity range: 5.6 - 9.3 cSt @100C
30-weight viscosity range: 9.3 - 12.5 cSt @100C
So the rating system is flawed, AFAIC, a 9.9 cSt oil is close enough to be called a 25W if one so desires...
I can only ask that you read what I wrote and apply some common sense. K. I am done for today.
LOL, talk about something in short supply here on BITOG...
No doubt the average owner is fine with the 5W-20... I even use it in my mom's '03 Mercury, but she's 81 and just putters around town, so the oil is seldom at full operating temp... Me, as I stated before my stuff is run hard, probably more so than 99% of the general public...
Originally Posted By: A_Harman
I do appreciate the comedic value of mixing 20-weight and 30-weight and ending up with a "25-weight", but that's just not how it works. The SAE viscosity rating system just does not allow it.
20-weight viscosity range: 5.6 - 9.3 cSt @100C
30-weight viscosity range: 9.3 - 12.5 cSt @100C
So the rating system is flawed, AFAIC, a 9.9 cSt oil is close enough to be called a 25W if one so desires...
Originally Posted By: Clevy
Originally Posted By: demarpaint
Originally Posted By: boxcartommie22
clevy, is that true about your uncle?miss information here could cost alot of people their engines..what about the tight clearances of the new modulars?is that a myth?
According to his uncle it seems 30 grade oil isn't good in that application either, which is interesting. From what I've read Ford tested the living [censored] out of those engines with the oil spec on the fill cap, in desert heat as well. IIRC Johnny was with the Pennzoil company during that time and he and I discussed the results at great length. He said the 20 grade oil did quite well.
Not what I wrote. I wrote that it was built for a 40 weight. And tested extensively with it. Then ford erred on the side of caution by specifying a 30 weigh. Then a few years later they back spec'ed everything with 5w-20. The ford Aussie models are all spec'ed to a 5w-30 still I believe. They use the same motors we do don't they. Why is it different there..... No CAFE laws and the aboriginals aren't complaining about air quality and blah blah blah. My uncle wayne started at ford in when he was 17 years old. Ford helped finance his education and he went from the line to r+d. He retired at 55 with a fat pension and a cottage on Georgian bay. I can only ask that you read what I wrote and apply some common sense. K. I am done for today. I probably stirred up a great big pile of poop here.
Seems these thick thin discussions get some people here really upset. I'm still waiting on the Fords running 20 grade oil to fill up the junk yards across the USA. In many parts of the world 20 grade oil is still in limited supply, which could be why it isn't used. Does CAFE play in? Sure, but I don't see these vehicles using 20 grade oils filling up junk yards either. Honda is pushing to go even thinner, you don't see Honda's running 20 grades having problems. Opinions vary, I follow what the mfg suggests as far as oil viscosity goes.
Originally Posted By: demarpaint
Originally Posted By: boxcartommie22
clevy, is that true about your uncle?miss information here could cost alot of people their engines..what about the tight clearances of the new modulars?is that a myth?
According to his uncle it seems 30 grade oil isn't good in that application either, which is interesting. From what I've read Ford tested the living [censored] out of those engines with the oil spec on the fill cap, in desert heat as well. IIRC Johnny was with the Pennzoil company during that time and he and I discussed the results at great length. He said the 20 grade oil did quite well.
Not what I wrote. I wrote that it was built for a 40 weight. And tested extensively with it. Then ford erred on the side of caution by specifying a 30 weigh. Then a few years later they back spec'ed everything with 5w-20. The ford Aussie models are all spec'ed to a 5w-30 still I believe. They use the same motors we do don't they. Why is it different there..... No CAFE laws and the aboriginals aren't complaining about air quality and blah blah blah. My uncle wayne started at ford in when he was 17 years old. Ford helped finance his education and he went from the line to r+d. He retired at 55 with a fat pension and a cottage on Georgian bay. I can only ask that you read what I wrote and apply some common sense. K. I am done for today. I probably stirred up a great big pile of poop here.
Seems these thick thin discussions get some people here really upset. I'm still waiting on the Fords running 20 grade oil to fill up the junk yards across the USA. In many parts of the world 20 grade oil is still in limited supply, which could be why it isn't used. Does CAFE play in? Sure, but I don't see these vehicles using 20 grade oils filling up junk yards either. Honda is pushing to go even thinner, you don't see Honda's running 20 grades having problems. Opinions vary, I follow what the mfg suggests as far as oil viscosity goes.
thanks clevy for your explantions..
Mixing 5-20 and 5-30 will thicken things up a bit.
Why not use it ?
Why not use it ?
On my last 3 oil changes on my vehicles I've mixed weights and brands. Why? Why not. Well, I had a bunch of partial containers sitting around and wanted to clean up a bit. I dumped three different brands of oil into a 5qt jug and did a change on my mini van on Monday. It was 1qt ST full syn 5w30, 1.5qts QSUD 5w-20, and 2.5qts of Valvoline syn power 5w-30. What's that all equal? 5 quarts of oil. I guess if you average it out it would look like 5w-27 but is it? Who cares, it works. I don't think my motor is going to try to seperate the weights. I've run straight 5w30 or straight 5w20 and never seen any difference in MPG so mixing the two shouldn't cause any problems. Mix away.
Originally Posted By: Clevy
Then a few years later they back spec'ed everything with 5w-20.
And they had to increase the oil sump capacity by 20%. Shell Australia site lists 5W-40 for ultimate protection. One does not have to have an uncle on the inside to put two and two together, but even the uncle won't help for the majority. Turns out to be a new religious debate.
of course, modern 5W-20 will withstand first 200k miles, but I need more
Then a few years later they back spec'ed everything with 5w-20.
And they had to increase the oil sump capacity by 20%. Shell Australia site lists 5W-40 for ultimate protection. One does not have to have an uncle on the inside to put two and two together, but even the uncle won't help for the majority. Turns out to be a new religious debate.
of course, modern 5W-20 will withstand first 200k miles, but I need more
i had the Mobil Syn HM 10W40 in my hand... Why did i go with the 10W30?? I should of went with the 10W40....
This ol gurl see's alot of throttle, highway and mountain driving, alot of shifts, hours of driving, multiple starts aday...
I was going to mix 3QTS 10W40, and 2 QTS 10W30, but using mobil QTS it would get expensive..
Maybe next oil change... in 6K miles..
I was going to mix 3QTS 10W40, and 2 QTS 10W30, but using mobil QTS it would get expensive..
Maybe next oil change... in 6K miles..
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You raise a good point.
You might ask what's so special about the lower specific output VAGs, MBs and BMWs that they need a forty grade, while the Ford Mod doesn't?
The Mod might live longer on a forty, but it will already outlive the car it's installed in on a twenty, so does it actually matter?
The life of a vehicle is rarely determined by the life of the engine installed in it.
You might ask what's so special about the lower specific output VAGs, MBs and BMWs that they need a forty grade, while the Ford Mod doesn't?
The Mod might live longer on a forty, but it will already outlive the car it's installed in on a twenty, so does it actually matter?
The life of a vehicle is rarely determined by the life of the engine installed in it.
If ran extremely hard like a track raced mustang i would think that a 5w40 or 5w50 synthetic would be the way to go. That is what ford specs for the ford gt or the shelby mustangs. When i asked a field service engineer about the thicker oils in the 3 valve modulars to reduce the cam phaser noise he told me the POTENTIAL issue would be the passages in the head and was using 15w40 in cold weather as an example. He never said for sure there would be damage but being as he would know way more about it than me and had a concern i would not chance it. Now any 5w oil 20 on up to 50 I wouldnt think twice about.
Originally Posted By: FMC
Would 0w40 work safely in a vehicle spec'd for 5w20 ?
I would be willing to try it in my own Ford that calls for 5w20.
It would work safely if you don't have any thinner oil requiring solenoid in the valve train or cam phaser. I used 5W-50 in my 2.0L Zetec which spec'd 5W-30. Other than losing mpg and tougher cold weather starting it ran fine. After 2 years I went back to 5W-30 and I got my mpg back and the cold starts were quiet again. It runs the best on the 5W-30 spec'd all around. It's a manual tranny so I can control the engine rpm's better.
For my 2002 F-150 with the 4.6 I just use the Motorcraft 5W-20 & Motorcraft FL 820S oil filter and all is good. I do rev the engine sometimes but mostly it's driven like a truck. It's a manual tranny truck so I have better control over the shifting.
I don't really believe you'll gain any real benefit by using 0W-40 oil in a engine spec'd for 20 weight oil.
Whimsey
Would 0w40 work safely in a vehicle spec'd for 5w20 ?
I would be willing to try it in my own Ford that calls for 5w20.
It would work safely if you don't have any thinner oil requiring solenoid in the valve train or cam phaser. I used 5W-50 in my 2.0L Zetec which spec'd 5W-30. Other than losing mpg and tougher cold weather starting it ran fine. After 2 years I went back to 5W-30 and I got my mpg back and the cold starts were quiet again. It runs the best on the 5W-30 spec'd all around. It's a manual tranny so I can control the engine rpm's better.
For my 2002 F-150 with the 4.6 I just use the Motorcraft 5W-20 & Motorcraft FL 820S oil filter and all is good. I do rev the engine sometimes but mostly it's driven like a truck. It's a manual tranny truck so I have better control over the shifting.
I don't really believe you'll gain any real benefit by using 0W-40 oil in a engine spec'd for 20 weight oil.
Whimsey
Originally Posted By: Whimsey
Originally Posted By: FMC
Would 0w40 work safely in a vehicle spec'd for 5w20 ?
I would be willing to try it in my own Ford that calls for 5w20.
I don't really believe you'll gain any real benefit by using 0W-40 oil in a engine spec'd for 20 weight oil.
Whimsey
You most certainly will if it's been modified for additional Hp like my Marauder, the added supercharger easily adds 175Hp at the wheels... Engine internals are 100% factory and yes it is specked for 5W-20, I use M1 0W-40 in it...
Originally Posted By: FMC
Would 0w40 work safely in a vehicle spec'd for 5w20 ?
I would be willing to try it in my own Ford that calls for 5w20.
I don't really believe you'll gain any real benefit by using 0W-40 oil in a engine spec'd for 20 weight oil.
Whimsey
You most certainly will if it's been modified for additional Hp like my Marauder, the added supercharger easily adds 175Hp at the wheels... Engine internals are 100% factory and yes it is specked for 5W-20, I use M1 0W-40 in it...
5w20 works well keeps the bearings cooler and flows faster use the 20
the mod will outlast the B.M.W. and M.B. almost anytime
my shop is full of BMW AND MB
my shop is full of BMW AND MB
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