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What weight oil do you use?

robvas

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Been running 5-40 or 10-40 (supercharged)
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Pony2015

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It is a trade-off between mpg and engine wear. Details at this LINK . As long as you are to the right of the nadir in the Stribeck curve, you are fine from an engine wear perspective, and not much to be gained from a higher viscosity oil, and the further to right of the nadir you move, the lower the mpg. For my 2017 GT PP with lower compression coyote Gen 2, the valve train and oiling system were optimized for 5w-20 as specified on the oil cap and manuals, and that is what I use -- I'll take the better mpg. If I was racing or running the engine at high temps, I would reconsider.
 
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sholxgt

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It is a trade-off between mpg and engine wear. Details at this LINK . As long as you are to the right of the nadir in the Stribeck curve, you are fine from an engine wear perspective, and not much to be gained from a higher viscosity oil, and the further to right of the nadir you move, the lower the mpg. For my 2017 GT PP, the oil cap specifies 5W-20, and that is what I use -- I'll take the better MPG. If I was racing or running the engine at high temps, I would reconsider.
Send a sample off for analysis and you will change your mind. 5w20 looks fine at first, but the viscosity break down gets ugly. Especially if you're using Motorcrap oil.
 

Farkel

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My '19 is also a daily driver. Based on the change in Ford's recommendations, as discussed in the various "Similar Threads" noted below, I switched to 5w-30 Motorcraft full synthetic. I also switched my oil cap. My Blackstone oil reports have always been excellent (even before I switched a few changes ago). I can't point to any specific benefits I have noted, but 5w-20 just doesn't seem like an appropriate oil weight for a high-performance engine.
I did the same, but I've never had the oil analyzed. Got the 5W30 cap from @LevittownFordParts.
 

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Like engineer mike I use either 5w-40 or 5w-50. I bought a 5w-50 oil cap.
 

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Free Spirit

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Getting ready to do my first change tomorrow and thinking of going with 5w30 instead of 20.

Car gets DD regardless of weather and M-F it sees a 80 mile round trip.

I don't track it but do a few WOT pulls each week. Might see the drag strip 1-2 times this year, maybe.


Wondering if stepping up to 30 will be beneficial, and what you guys run.
Having learned from s197 ownership, Ford used the 5w20 for epa reasons and it would cause long-term engine damage as revealed by the engineer who designed the car, I wouldnt be surprised at all if the same thing holds true with the 5.0 I always run the proven oil. Pennzoil ultra Platinum 5w30. Consistently outperforms amsoil and every single other brand as well has having the most and best additives for keeping the engine alive and healthy. Oh and if you start using it before I think 75k miles and/or 7 years, whichever comes first then you can sign up for the warranty. Basically if your engine fails before 500k miles they will replace the engine for free provided you keep the receipts for your oil purchases. Easy enough for a dirt cheap engine warranty imo. But usiing their stuff you won't have an engine fail. Top notch shit. Always always always pair my good oil with a wix xp filter. (Again, shown to outperform the competition in terms of flow and filtering, you can get other filters that filter smaller particles. But they reduce flow compared to wix)
 
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Zrussian13

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Having learned from s197 ownership, Ford used the 5w20 for epa reasons and it would cause long-term engine damage as revealed by the engineer who designed the car, I wouldnt be surprised at all if the same thing holds true with the 5.0 (they are tough motors, I ran mine fully drained, oil plug off for hours because I forgot I hadn't finished the oil change after I let it drain for 6+ hours). I always run the proven oil. Pennzoil ultra Platinum 5w30. Consistently outperforms amsoil and every single other brand as well has having the most and best additives for keeping the engine alive and healthy. Oh and if you start using it before I think 75k miles and/or 7 years, whichever comes first then you can sign up for the warranty. Basically if your engine fails before 500k miles they will replace the engine for free provided you keep the receipts for your oil purchases. Easy enough for a dirt cheap engine warranty imo. But usiing their stuff you won't have an engine fail. Top notch shit. Always always always pair my good oil with a wix xp filter. (Again, shown to outperform the competition in terms of flow and filtering, you can get other filters that filter smaller particles. But they reduce flow compared to wix)
I can't tell if this is a joke or a really weird plug for certain oil products...
 

Mach1Racer

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Mobil 1, sadly, isn't what it used to be. Their regular versions no longer use a synthetic base stock. It's not even legally synthetic in other countries. That's why you see the "European" versions where it is actual synthetic and carries a different API certification. So, if using Mobil 1, you want the European version or possibly the Extended Performance version.
Can you provide literature or proof of this statement for CURRENT Mobil 1 oils in 5w-30 and 5w-50?

“European” oil is built in consideration of cars with Desil and Turbo Desil engines. The vast amount American vehicles don’t offer a Desil option.

Desil engines generate higher levels of soot which is not often found in gasoline engines. European formulated oils are engineered to combat this whether they are Group 2, 3, or 4 oils.
 

robvas

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Mpg difference is a fraction of 1mpg for each weight of oil
 

G.T.

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... (they are tough motors, I ran mine fully drained, oil plug off for hours because I forgot I hadn't finished the oil change after I let it drain for 6+ hours)
Wow!
 

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2015 Silver GT

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Mobil 1, sadly, isn't what it used to be. Their regular versions no longer use a synthetic base stock. It's not even legally synthetic in other countries. That's why you see the "European" versions where it is actual synthetic and carries a different API certification. So, if using Mobil 1, you want the European version or possibly the Extended Performance version.
This. Mobil 1 changed their formula many years ago and it is no longer a “true” synthetic. It’s nothing special now.
 

Free Spirit

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I can't tell if this is a joke or a really weird plug for certain oil products...
I mean do your own independent research. Everything I said is a fact. I'm just sharing what products are best for long-term engine survival. They asked what weight I use I said what weight and why. Again, everything can be verified as fact
 

MAGS1

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5w50 m1. I never ran 5 20 ever in my modular fords. I worked a limo place in the early 2000s and ran town cars and marquis. They also were a moving company. I asked the machinic what they ran in the limos for oil. He said they just ran the same 15 /40 Rotella in them as the trucks. I said "you know they call for 5 20" he said they get 500k out of them without a problem so wasn't going to change a thing.
 
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K Myers

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Getting ready to do my first change tomorrow and thinking of going with 5w30 instead of 20.

Car gets DD regardless of weather and M-F it sees a 80 mile round trip.

I don't track it but do a few WOT pulls each week. Might see the drag strip 1-2 times this year, maybe.


Wondering if stepping up to 30 will be beneficial, and what you guys run.
5w20 is used by the manufacturer for EPA and optimum fuel efficiency. I changed to 5w30 mobile 1 full synthetic with Ceratec, with no issues I have 88k with a ESS g3. FYI so you can make your own decision look at oil geek on you tube
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