5-20 oil?
Elder User
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I'm more concerned with higher ambient temperatures where I live. It hardly will ever get below 35°F during winter months of Jan-Feb only, but summers are brutal at 105°F and running the air at the same time. Just seems to me that going up to 30 weight would give me a little more protection.
Also, I found this statement:
Motor Oil Viscosity
Also, I found this statement:
Motor Oil Viscosity
Look at Mobil 1 5W-30 and 10W-30.
Mobil 1 10W-30 is 10.0 cSt at 100 deg C
Mobil 1 5W-30 is 11.3 cSt at 100 deg C
Mobil 1 10W-30
Mobil 1 5W-30
Meaning, that M1 5W-30 is actually a bit thicker at higher temps than M1 10W-30. Cold flow pump-ability and high temp viscosity should really be judged on a case-by-case basis.
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Joined: Dec 2003
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From: Iowa
I agree 5w-20, 5w-30 and possibly 10w-30 would be fine. but to say they didn't use the lighter oil because of tighter clearences is what i was arguing here. And the reason they use the 5w-50 in those modular engine is due to the high temps and fuel dilution that occurs in hi-performance and supercharged engines
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http://www.dantheoilman.com/fordoilfaq.doc
Q: Why did Motorcraft® release SAE 5W-20 motor oil?
A: It was the right thing to do for the consumer and for the environment. It was one of Ford's first steps in working to improve the fuel economy of our SUVs by 25% by the 2005 calendar year. SAE 5W-20 improves fuel consumption by approximately 0.6 percent. For the 2001 fleet, this amounts to reducing fuel usage by more than 21 million gallons per year. This reduction in gasoline consumption leads to a reduction in carbon dioxide emissions by 190,000 metric tons per year, which is equivalent to taking nearly 23,100 cars and trucks off the road each year.
B. Ford Motor Company has a responsibility to make its vehicles more environmentally friendly plus this is a better oil. Also, the industry is converting from GF2 level products to GF3 and Motorcraft 5W-20 is leading the way for our product line up.
Q: What if a fleet wants to use 10W-30 instead of 5W-20, is that problem?
A: If these are gasoline engines, a 10W-30 is okay. However, why wouldn't they want to take advantage of the fuel economy savings and superior engine protection of a 5W-20. Remind them that 10W-30 is two oil generations old."
And before you quote it, the references to 5W-20 offering superior protection were based on their 5W-20 at the time meeting GF-3 while their 5W-30/10W-30s were only GF-2. We are coming up on GF-5 soon.
And the reason they use the 5w-50 in those modular engine is due to the high temps and fuel dilution that occurs in hi-performance and supercharged engines
Postmaster
Joined: Oct 2009
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Lets see, according to Ford the 5w20 does offer superior protection. That does mean that something that offers inferior protection is a problem and a downgrade. I don't think it can be spelled out more clearly. Slightly lower friction is always better for the engine.
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From: SUNMAN INDIANA
you can't even compair a gt & gt500 motors to a 5.4l found in a truck. i would venture to say they don't share one internal part. the gt is a dry sump system. modular is an engine family. just because it is a modular doesn't mean that they are made equal. 352, 360, 390, 410, 427 & 428 are all in the same family and share a common structure, but are not the same
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First of all, replying to all of these posts...the 'w' in the viscosity grade '5w30' or '10w30' stands for 'winter', so it doesn't matter if 5w30 or 10w30 is used when the temps are hot anyways. And plus, research data shows that a 10w30 oil will break down to a 5w30 oil after 3000 miles anyways.
Second of all, if the owner's manual states 5w30, then you can't go wrong with 5w30...that's what the engine is designed for. My '98 F150 5.4 has been run on 5w30 since it came off the assembly line (I'm the original owner)....It has 133,000 miles on it and has run in temps ranging from -10 degrees in Montana and 110 degrees in Arizona...and it's still running like a champ and not a single oil leak from anywhere (valve covers, seals, etc...).
That's my 2 cents on the topic...take it or leave it.
Second of all, if the owner's manual states 5w30, then you can't go wrong with 5w30...that's what the engine is designed for. My '98 F150 5.4 has been run on 5w30 since it came off the assembly line (I'm the original owner)....It has 133,000 miles on it and has run in temps ranging from -10 degrees in Montana and 110 degrees in Arizona...and it's still running like a champ and not a single oil leak from anywhere (valve covers, seals, etc...).
That's my 2 cents on the topic...take it or leave it.
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Read the language used. Their claims of "superior protection" were based on their 5W-20 of the time meeting GF-3 standards, at the time Motorcraft 5W/10W-30 only met GF-2. This is all spelled out very clearly in the Q&A. The thinner viscosity wasn't their reasoning for claiming 5W-20 offered superior engine protection.
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I'm just wondering how many people here claiming that thick oils is so horrible for Modulars actually know their way around a Mod motor. Very few, I'd guess.
the gt is a dry sump system.
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I can back that up too, I am running Royal Purple 5w30 in my '94 Aerostar which has over 220,000 miles now. It has no oil leaks, has great compression, produces great power, and I change my oil between 15,000 - 20,000 miles. My brother had the same van but a couple years newer, ran Quaker State 10w40 in it one time, had valves give out on him 5 weeks later. I have not had a complete opportunity to start measuring the old valves and head and I bought a prebuilt heat with new valves ready to bolt on. But two valves are definitely sticking. Hard to tell if its related, but I am the once fixing it, and I am finding a lot of abnormal wear on the pushrods and lifters. I suspect that this is startup wear because the heavier oil does not flow as well. All his problems because to occur shortly after his quick lube oil change with the wrong oil.
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