Will Thinner Oils Damage Your Engine?
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Will Thinner Oils Damage Your Engine?
I'm not going to find out.
I'm not going to find out.
I have posted on here several times over the years about the use of straight 20 weight oils in pickups. When I was in grad school at the University of Illinois from 1969-1973, almost all the pickup truck owners I knew out there ran straight 20 weight oil year round. Those trucks ran into the 150,000 mile range regularly with no noticeable oil related engine problems. And they were NOT designed for that weight oil.So I always have to smile when I read posts like this.. No, they won't. I use 0W-20 VW 508 oil in my 2019 Passat and get great mileage and driveability.
required listening for mechanics who insist 5W-30 is "too thin" for cars requiring 10w-30
Yes but back then (pre-SAE J300) the equivalent HTHS of a 20-grade was around 2.9 to 3.0, so it was a different 20-grade then.
thread.With temporary shear a 0W-40 Synthetic drops from 3.8 HTHS to 3.34. That's less than a typical SAE 30.
Multi-Grades also experience more permanent shear than straight weights.
My point is that 20 Grade likely had at least the operating viscosity of 10W-30.
In the latest Hot Rod, Ken Duttweiler uses Lucas 20W50 in his 400mph+ Bonneville record holding turbo V8s, so it should be good for a Prius, right?
The problem with the whole viscosity issue is people "want" there to be a single, direct answer. For example - 0w20 undoubtedly offers the best protection for my engine etc. Reality is viscosity and engines are somewhat dynamic. Most engines can be run on multiple grades within reason. Operating conditions vary, hp vary, life expectancy varies....the list goes on and on. I believe in what the OEM recommends. One could argue that is based on cost cutting, mpg and an operating life cycle of only 150k miles. Possibly. There is a range of possibilities that exist.
Short tripped during a Minnesota Winter 0W-16 is great. At 300F Oil Temps on the track not so much.
As you say, no one answer exist.
I'll read all about it here, I passed with my vehicles on finding out.
If only I drove enough to have fun with oil. Despite misgivings of the owner, I'm using the Toyota(EPA) spec 0w20. It gives me the same giddy feeling as driving without my seat belt on. There is no margin for fuel dilution, etc. I once had an overheat so bad it ended with a detonated piston. destroyed head,etc.. replaced parts from junker, rod and piston, re-used rod shells they were perfect. I put another 50 k on the engine I was running 20w50 at the time. Made me a believer in thick oil. Maybe my '16 Camry is built to tighter tolerances that can handle a "smaller wedge"of hot 0w20. I hope so.
It's important to remember too that moving to 20 and now 8 grade oils was strictly due for fuel economy reasons. That is a fact and not up for debate. However, in doing so, obviously the oils had to be made so they are robust enough and they've proven to be so. If one considers 150k-200k miles a respectable life cycle, you'll likely not have any issues with the OEM grade. That's also 13-17 years of ownership if you average 12k per year, far longer than most even want to keep a vehicle.
I'm curious how the German Audis and BMW's running the 0w20's are going to hold up. That's more a test than the vast majority of the Japanese and N/A brands running 0w20.
I'm curious how the German Audis and BMW's running the 0w20's are going to hold up. That's more a test than the vast majority of the Japanese and N/A brands running 0w20.
He dumbs things down pretty well. While following the manual is always the right choice, the manual also makes compromises. It doesn't know if the vehicle is being used in Florida or Alaska, for example. If the manual says 5w-30 and you live in Florida, a 10w-30 will be perfectly fine.
I wish he'd gotten into HTHS. Maybe in a future video.
I wish he'd gotten into HTHS. Maybe in a future video.
Selecting oil by HTHS and ambient temps is a better determinator per your application than straight visc. Its a shame some oil manufacturers hide HTHS. As many have said, there is no "right" answer, it depends on your application and weather. IMO OEMs have gone the route to reccomemnd thin oils because they are usually synthetic, universal, and get better EPA numbers.
Perfect example: my miata skyactiv 2.0 rev's to 7500 and most of the 186hp is above 4k RPM. The first gear is very short peak torque comes at 4k RPM. The car is manual and my driving style is vastly different from grandma driving her automatic skyactiv 2.0 in a mazda3. Usually the automatics keep the rev's low due to different gear ratios. Both car's are spec'd to 0w20 (HTHS ~2.7). Mazda "allows" 5w30 in europe and mexico. Higher HTHS = higher rpm protection. Going forward, I'll be using an HTHS 3.5 oil. Driving around my equinox, I have no reason to change from OEM spec 0w20 unless an UOA suggests otherwise.
Case in point: my gilfriend has a 2018 camry 2.5l that spec'd for 0w16. That transmission does absolutely everything in its power to keep the rev's down, it will even upshift by itself in manual mode. Lower rev's = sufficient low HTHS protection. It was so bad that toyota had to release a transmission software update to correct "jumpy" starts at low speeds.
Perfect example: my miata skyactiv 2.0 rev's to 7500 and most of the 186hp is above 4k RPM. The first gear is very short peak torque comes at 4k RPM. The car is manual and my driving style is vastly different from grandma driving her automatic skyactiv 2.0 in a mazda3. Usually the automatics keep the rev's low due to different gear ratios. Both car's are spec'd to 0w20 (HTHS ~2.7). Mazda "allows" 5w30 in europe and mexico. Higher HTHS = higher rpm protection. Going forward, I'll be using an HTHS 3.5 oil. Driving around my equinox, I have no reason to change from OEM spec 0w20 unless an UOA suggests otherwise.
Case in point: my gilfriend has a 2018 camry 2.5l that spec'd for 0w16. That transmission does absolutely everything in its power to keep the rev's down, it will even upshift by itself in manual mode. Lower rev's = sufficient low HTHS protection. It was so bad that toyota had to release a transmission software update to correct "jumpy" starts at low speeds.
It would be nice if SAE J300 could be redone to show CCS-HTHS, but that would confuse a lot of people.
The question as asked is both non sequitur and too broad to be answered with any degree of accuracy and reliability.
The minimum required viscosity is a function of design ( clearances, tolerances, pressures etc.) and loading ( torque, speed, duty cycle etc.)
There's also a built in range and of course all that hidden data on the actual stress analysis.
There's nothing wrong with experimenting and determining a more appropriate application specific viscosity and additive package but I suggest doing it carefully
The minimum required viscosity is a function of design ( clearances, tolerances, pressures etc.) and loading ( torque, speed, duty cycle etc.)
There's also a built in range and of course all that hidden data on the actual stress analysis.
There's nothing wrong with experimenting and determining a more appropriate application specific viscosity and additive package but I suggest doing it carefully
The guy in the video “answered“ it by saying bad things can happen.
It's common to hear people complain of how manufacturers and blenders "hide" stuff, but HTHS isn't hidden at all. Sure some producers may not publish values (or may publish nominal values) but the grade gives a range, it's really a fool's errand to chase "higher HTHS" values within a grade. If you really want a high HTHS oil then go up in grade, you'll get what you want by doing so. It's also why approvals are important since many European approvals require a minimum HTHS as part of the approval process. You want a higher HTHS oil? Then get one with an approval that requires the HTHS you are seeking.
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