I run mobil 1 5w50 (have a couple dozen cases from a a very good deal a while back, guess what this toyota is going to live most of it's life on...) in a modern vvt engine. Runs great, no codes, even below zero.
VVT and thicker oil
- Thread starter Scott S
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I have done that but really this is more thickie love rather than experimentally backed evidence. Anyway, no one is going to nail this one. Car engines using the low viscosity oils do just fine and most vehicles are junked for other reasons other than engine failure.
There is experimental evidence, lots of controlled wear studies have been done that show more HTHS results in less wear. Anyone who understands Tribology knows that. Viscosity is the main mitigator of wear between moving parts. I knew it would come down to "the car will rust out, get wrecked or be junked before the engine fails" mantra, lol. It's not about "engine failure", it's about reducing wear and keeping the engine more mechanically healthy over it's lifetime.
But it could however mean actual engine failure if someone used too thin on track duty. There was a YouTuber who tracked his car with 5W-20 because he thought it would keep oil temps down, but instead he wiped out his journal bearings - and he wondered why.
Time for you to post an SPE paper. The study should show an engine that specs 0W20 or 5w20. Then the lab would run the same engine on 5w30. They run both engines at similar conditions, tear the down and compare the two. Doesn’t that sound simple? Surely that paper must be out there. What you’ll find is that at normal operating conditions there was no appreciable difference in wear. The engineers know this.There is experimental evidence, lots of controlled wear studies have been done that show more HTHS results in less wear. Anyone who understands Tribology knows that. Viscosity is the main mitigator of wear between moving parts. I knew it would come down to "the car will rust out, get wrecked or be junked before the engine fails" mantra, lol. It's not about "engine failure", it's about reducing wear and keeping the engine more mechanically healthy over it's lifetime.
But it could however mean actual engine failure if someone used too thin on track duty. There was a YouTuber who tracked his car with 5W-20 because he thought it would keep oil temps down, but instead he wiped out his journal bearings - and he wondered why.
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Recall track duty with elevated temps is a separate issue as outlined in posting #97.There is experimental evidence, lots of controlled wear studies have been done that show more HTHS results in less wear. Anyone who understands Tribology knows that. Viscosity is the main mitigator of wear between moving parts. I knew it would come down to "the car will rust out, get wrecked or be junked before the engine fails" mantra, lol. It's not about "engine failure", it's about reducing wear and keeping the engine more mechanically healthy over it's lifetime.
But it could however mean actual engine failure if someone used too thin on track duty. There was a YouTuber who tracked his car with 5W-20 because he thought it would keep oil temps down, but instead he wiped out his journal bearings - and he wondered why.
Plenty of more sophisticated studies than that have been done, using irradiated parts to monitor wear in real time. SWRI was one of the places that do that kind of wear studies. Sounds more like time for you to do some self research on the subject matter.
Yeah, like said ... stems back to reduced MOFT due to less viscosity means more wear. Some level of that can also happen in normal street driving too, depending on use conditions. Why do you think Toyota has that use thicker oil for harder use conditions statement in the OM if they don't know that thicker oil provides better engine wear protection? Nobody here is claiming that using thinner oil for normal street driving is going to "blow-up" an engine.
To summarize. Do you advocate engines spec’d for 5w20 use 5w30 and engines spec’d for 5w30 use 5w40? I’m saying you would not notice the difference in the wear. ( tracking at high oil temperatures not included.) I’m signing out now.
I would use a 5W-30 in any engine speced for xW-20, regardless of driving conditions because I like HTHS viscosity protection headroom. I'd use xW-40 in anything I used for track use unless the manufacture (like Ford) recommended something thicker like xW-50 for track use. Just because you "would not notice a difference in the wear" from behind the steering wheel doesn't mean there isn't an actual difference in wear happening - regardless of how small. Having wear protection headroom ensures that the long term wear is minimal under all anticipated use conditions, and the engine stays in top mechanical condition over it's lifetime. Some manufacturers like Ford actually went up a grade in viscosity on the Coyote after specing 5W-20 for years, for reasons greater than the CAFE credits they lost in doing so.To summarize. Do you advocate engines spec’d for 5w20 use 5w30 and engines spec’d for 5w30 use 5w40? I’m saying you would not notice the difference in the wear. ( tracking at high oil temperatures not included.) I’m signing out now.
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For the 800th time.
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My new car (the MG) gets 0W-20 from the factory, but next week 10W-30 full synth is going in. I'll let you know how it goes.
I think we got our wires crossed a bit. You said if you lived in Australia you’d own a diesel HiLux. I questioned why you’d want a HiLux as they are awful (I am Australian and HiLuxes are everywhere – they are among the worst utes to drive, suspension is back-breaking, powertrain is not that great and reliability is not as good as people make it out to be).
Got it.
I drove a "Dual Cab HiLux" in Fiji and had some fun.
The vision is for durability, not a breezy daily commute in Sydney.
I am sure you are right, friend.
If the HiLux was still available with the 4.0L V6 gas then sure, but the 1GD 2.8L diesel is a boat anchor of an engine. Not good at all.
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