Switching back to 5W20 (SuperTech) for mpg!

+1 for another case of BITOG psychosis where members are absolutely sure what they see or hear must be due to their choice of oil. What little research I've seen suggests a maximum difference of 1% when going down a single grade and so for the cars I drive that means a maximum increase of 0.15mpg, 0.20mpg, and a whopping 0.32mpg which statistically could also be explained by a 8.96mph headwind, a family member being in the car a little more often than normal, my son asks me if I can drive Ethan and Chris home from practice when I usually don't, refilling the gas tank at half full vs 1/4 full, temperature, weather, was I running late one day and I was a little more aggressive with the throttle, slight deviations in my route or routine, differences in traffic patterns, etc, etc, etc, etc.

BITOG is a fun place to discuss a whole lot of things with some very thoughtful people but many here are pisspoor scientists and statisticians who want to ascribe certain observations to oil that they just have no right ascribing under their chosen testing methods - n=1 butt dynos, the color of the oil, the smell of the oil, the sound of the engine, 1% mpg differences - none of which has ANY statistical significance and can just as easily be explained by a million other variables besides oil - as has been said there's just too much noise in these scenarios.
 
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I live on L.I. a little under 25 miles from NYC. We can get cold snaps taking us down to 0F or on occasion below. What a lot of people might be missing in their recommendations for 10W20 for example is many NY'ers travel upstate where it can easily go to -30F or colder. I make those trips on occasion. PA is two hours from here, it gets pretty cold there too. Knowing how and were vehicles are driven should be considered before making recommendations. Just because a person lives in an area where it doesn't get insanely cold doesn't mean the car isn't driven to those places.
 
I live on L.I. a little under 25 miles from NYC. We can get cold snaps taking us down to 0F or on occasion below. What a lot of people might be missing in their recommendations for 10W20 for example is many NY'ers travel upstate where it can easily go to -30F or colder. I make those trips on occasion. PA is two hours from here, it gets pretty cold there too. Knowing how and were vehicles are driven should be considered before making recommendations. Just because a person lives in an area where it doesn't get insanely cold doesn't mean the car isn't driven to those places.
Very strange that some plan to eliminate natural gas heat there 🧐
 
Very strange that some plan to eliminate natural gas heat there 🧐
A lot of strange things here, lol. Natural gas is heating my house as I type this. I thought we were going to be out of NY, and I got lazy this year, then greed drove the price of firewood through the roof so I didn't buy any. I'll be cursing the price for natural gas when they adjust my budget up after the winter. I have a handle on some free firewood, as soon as I get a few things sorted out here I will grab it.
 
One thing that I discovered on my cross-country drive is that the way the car "feels" may not reflect its actual performance.

There were days when the Camry felt that it was sluggish, or that my driving situation suggested a drop in mileage (like through mountainous terrain), but a check at the gas pump when filling the tank showed otherwise.

One of the best mileage figures I got was when I "felt" that the car wasn't doing well. I fully expected the mileage to be at the lower end of the spectrum when it was, in reality, the best tank I achieved to that point.
Might have been running lean?
 
+1 for another case of BITOG psychosis where members are absolutely sure what they see or hear must be due to their choice of oil. What little research I've seen suggests a maximum difference of 1% when going down a single grade and so for the cars I drive that means a maximum increase of 0.15mpg, 0.20mpg, and a whopping 0.32mpg which statistically could also be explained by a 8.96mph headwind, a family member being in the car a little more often than normal, my son asks me if I can drive Ethan and Chris home from practice when I usually don't, refilling the gas tank at half full vs 1/4 full, temperature, weather, was I running late one day and I was a little more aggressive with the throttle, slight deviations in my route or routine, differences in traffic patterns, etc, etc, etc, etc.

BITOG is a fun place to discuss a whole lot of things with some very thoughtful people but many here are pisspoor scientists and statisticians who want to ascribe certain observations to oil that they just have no right ascribing under their chosen testing methods - n=1 butt dynos, the color of the oil, the smell of the oil, the sound of the engine, 1% mpg differences - none of which has ANY statistical significance and can just as easily be explained by a million other variables besides oil - as has been said there's just too much noise in these scenarios.
72r4nm.jpg
 
Honestly, I dont have the time to sit there with a stopwatch and record the 0 to 60 times or conduct any kind of scientific study. I drive very often and know what it feels like and with the 5W20 it felt peppier and there was more response from the throttle. The reader of the post should know that my feelings are subjective if no data is posted. I do spend more time in my cars then the usual commuter spends in their cars so I tend to notice things a lot more then the usual consumer.
It likely felt "peppier" because you wanted it to/had an expectation. There is no mechanical reason for it. A blind test would likely yield you telling me it was peppy or not based solely on that pre-conceived expectation (lighter oils are "faster" than heavier oils) even if during each test run I kept the same oil (regardless of grade) in the vehicle.
 
I'm kind of an hypermiler myself and i've stopped chasing fuel economy through oil viscosity after doing my best tanks with 15W40 in the sump. Driving conditions, the way you drive and tire pressure have so much more to do with MPG.

That being said, i don't see the benefit of running anything heavier if xW20 is ok for your engine and you care about fuel mileage. Since you care about MPG, i don't think you will drive it agressively, one less reason for a heavier oil.
 
When you can't resist the random deals and end up with a stash of nearly 100qts of 5w-30 you end up with a compelling reason.. I can say for my part I have 3 vehicles spec'd for 5w-20 running 5w-30 currently and I haven't noticed any difference in MPG's or how they sound/run/rev.
That I get, what I don't get is people who run a heavier oil because they think 5W-20 is too thin to protect...
 
That I get, what I don't get is people who run a heavier oil because they think 5W-20 is too thin to protect...
In their daily driven basic run-of-the-mill vehicle that probably never sees above 3K RPM....
 
I've never noticed any mpg differences between 5W30 or 5W20/0W20.
I only notice the difference in mpg between seasons. Summer/better...Winter/worst.
My Ford 2 liter engine - after 5W20 AND fuel dilution knocked the heck out of the engine - got BETTER long term fuel mileage average on 10W30 versus 5W20 (with only 2550 miles on that oci) and that OCI was started at the tail of Winter 2022 with some 20 deg starts. 1.5MPG improvement first week and continuing throughout the OCI.

Maybe the K sensor was quelled by the velvet cushion of the stupendous Quaker State FS 10w30.
 
In their daily driven basic run-of-the-mill vehicle that probably never sees above 3K RPM....
I’m starting to see the “Fuel dilution can possibly mess that up” side of this discussion (in this discussion we are talking about.

Edit: Especially if it is “short tripped” a lot, or never fully warmed or not always.. short trips.. operating temp..
 
I’m starting to see the “Fuel dilution can possibly mess that up” side of this discussion (in this discussion we are talking about.)
Yes that is true. In our Atlas that my wife daily drives, it's just an around town vehicle and the 3.6 VR has quite a bit of fuel dilution but 5K changes with a VW502 or 504 oil is just fine in a vehicle that again...isn't being beat on.
 
I dont like using the thin stuff but am forced to because of mpg concerns and trying to squeeze out the last bit. The 3.7 Liter Duratec calls for 5W20, but I have used 5W30 and 5W40 in the past. So I put SuperTech 5W20 Advanced in it and I notice immediately the engine is a bit peppier and faster. Seems to run better with the 5W20. My observations in the past was the thicker stuff quieted the engine down overall, but there was a bit of performance lag.

It seems like all my decisions nowadays are trying to increase the mpg with gas prices north of $3...lets hope the 5W20 can squeeze a little bit more mpg out of this engine.
*I noticed the same performance increase running 5W20 (stamped on the oil cap) of my Hyundai 2.4L non - turbo GDI engine - but I decided against it in favor of 5W30 (allowed for this engine) . The reason is because of noted fuel dilution issues with this engine as well as bearing issues requiring greater film thickness for engine longevity / safety margin. The fuel dilution issue is enough of a concern not to use 5W20 in this engine as at 4K miles it essentially is now a 5W16 oil .
 
*I noticed the same performance increase running 5W20 (stamped on the oil cap) of my Hyundai 2.4L non - turbo GDI engine - but I decided against it in favor of 5W30 (allowed for this engine) . The reason is because of noted fuel dilution issues with this engine as well as bearing issues requiring greater film thickness for engine longevity / safety margin. The fuel dilution issue is enough of a concern not to use 5W20 in this engine as at 4K miles it essentially is now a 5W16 oil .
Even if an oil is “shear stable” or won’t shear or “in grade shear” or “shear down”… that fuel dilution..
…could be a problem..
 
I can tell the difference between 5W-20 and 5W-30 in my Hyundai Sonata 2.4 GDI. I’ve never noticed a difference in any other vehicle I’ve owned, and I would’ve said you’re crazy if you said you felt a difference. After owning the Sonata, I don’t doubt anyone who says they can tell a difference.

Like @ChrisD46 said, the Theta II 2.4 is peppier using 5W-20.
 
I believe that it has less to do with oil grade(to a point) and more to do with the whole shabang of things that a manufacture builds into a vehicle. Such as:

*lower weight
*more efficient drive train combo(engine/tranny/gearing)
*aerodynamics
*lower resistance tires
*yes, oil grade too

*lower speed driving/more efficient trips...In other words, if you have to do lot of errands, drive to your furthest destination first so the engine warms up properly and work your way back home. Don’t drive to the closest place first, then the next and on & on til you get to the furthest destination. The engine won’t warm up as efficiently doing it this way...And less junk in the trunk.

But I think that if someone wanted to get better fuel economy e.g., just by changing to an LRR tire alone, that they’d be hard pressed to see a huge difference in economy. It takes a lot of the above combined to see the gain. Another example, I never saw a single bit of fuel economy savings by removing the roof rack/cross bars on our SUV…Nothing!
 
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