Can thicker oil prevent rocker arm failures in Pentastar 3.6 V6?

[ZeeOSix]

Only thing being avoided is the actual facts that I asked about proof on the 3.6 pentastar having additional wear from off-roading and rock crawling running 0w20. Was any actual tests done where two 3.6 pentastar’s were run through the same conditions one with a 20wt the other 30wt then torn apart for examination? Or is this simply yet another hijacked thread to start a thick thin debate?

Too many variables are involved, and it really hinges on how the engine is used. If the oil is getting a lot hotter, and the engine is being lugged down with high loads at low RPM then a thicker oil (based on the science of Tribology) will indeed give more engine protection headroom. What it boils down to is the fact that thicker oil (more HTHS) under the same operating conditions will give larger film thickness between moving parts, and therefore more wear protection. I care less about what other use (even though I post about why viscosity might matter), but I always bump up from a recommended xW-20 to a 5W-30. No engine specifying a xW-20 is going to suffer any consequences whatsoever from using a 5W-30 ... except maybe 0.01 MPG less fuel mileage. Not worth it to me to sacrifice more engine protection for a tiny sliver of fuel mileage that would be negated for the whole tank of gas by one high throttle row through the gears from a stop light, lol.

If you were using your engine hard, would you rather possibly be on the edge of losing full protection if you got into a surprise severe driving condition, or would you rather have some protection headroom and insurance? That's basically why people will run one viscosity grade higher than what the auto makers recommendation which is primarily driven by CAFE to sacrifice some possible engine wear for a small gain in fuel mileage.

 

[Schandyman]

Too many variables are involved, and it really hinges on how the engine is used. If the oil is getting a lot hotter, and the engine is being lugged down with high loads at low RPM then a thicker oil (based on the science of Tribology) will indeed give more engine protection headroom. What it boils down to is the fact that thicker oil (more HTHS) under the same operating conditions will give larger film thickness between moving parts, and therefore more wear protection. I care less about what other use (even though I post about why viscosity might matter), but I always bump up from a recommended xW-20 to a 5W-30. No engine specifying a xW-20 is going to suffer any consequences whatsoever from using a 5W-30 ... except maybe 0.01 MPG less fuel mileage. Not worth it to me to sacrifice more engine protection for a tiny sliver of fuel mileage that would be negated for the whole tank of gas by one high throttle row through the gears from a stop light, lol.

If you were using your engine hard, would you rather possibly be on the edge of losing full protection if you got into a surprise severe driving condition, or would you rather have some protection headroom and insurance? That's basically why people will run one viscosity grade higher than what the auto makers recommendation which is primarily driven by CAFE to sacrifice some possible engine wear for a small gain in fuel mileage.

I just stick by the book. And not me personally but a co-worker of mine pulls a 20’ plus boat trailer and landscaping trailer with a tundra that he runs 0w20. My fathers friend has a f150 ecoboost pulls a car and horse trailer runs 5w20 I’m sure there’s a large majority of people not stepping up oil weights but as the saying goes different strokes for different folks.

 

[kschachn]

Only thing being avoided is the actual facts that I asked about proof on the 3.6 pentastar having additional wear from off-roading and rock crawling running 0w20. Was any actual tests done where two 3.6 pentastar’s were run through the same conditions one with a 20wt the other 30wt then torn apart for examination? Or is this simply yet another hijacked thread to start a thick thin debate?

That’s not at all how you measure wear between two oils and obtain valid results. And the results have been posted here many times. Lower HT/HS oils have more wear, no two ways about it. It’s physics.

 

[kschachn]

I just stick by the book. And not me personally but a co-worker of mine pulls a 20’ plus boat trailer and landscaping trailer with a tundra that he runs 0w20. My fathers friend has a f150 ecoboost pulls a car and horse trailer runs 5w20 I’m sure there’s a large majority of people not stepping up oil weights but as the saying goes different strokes for different folks.

Hopefully this response indicates you finally understand the facts.

 

[ZeeOSix]

I just stick by the book. And not me personally but a co-worker of mine pulls a 20’ plus boat trailer and landscaping trailer with a tundra that he runs 0w20. My fathers friend has a f150 ecoboost pulls a car and horse trailer runs 5w20 I’m sure there’s a large majority of people not stepping up oil weights but as the saying goes different strokes for different folks.

Yep, xW-20 works OK for most, and most people wouldn't know anyway by sitting behind the wheel if their engine was slowly wearing out a bit faster. But all the "thickies" are saying is that a higher viscosity may give added protection headroom for when driving conditions bet tougher. I'm personally into headroom for a lot of things in life, lol.

Again, it all depends on the use circumstances. Those vehicles you mention may have adequate oil coolers and keep the oil temperatures down. You could run 0W-8 in a vehicle specifying 10W-40 if you kept the oil temperature of the 0W-8 down to where the viscosity was about equal to the 10W-40 at 275 F. It's all about oil temperature, and what the oil's viscosity is at those temperatures, because the viscosity between the moving parts does matter.

 

[Schandyman]

Jeep should put out a revision in the owner’s manual for off-roading to use a suitable 30wt depending on climate.

 

[Jackson_Slugger]

Too many variables are involved, and it really hinges on how the engine is used. If the oil is getting a lot hotter, and the engine is being lugged down with high loads at low RPM then a thicker oil (based on the science of Tribology) will indeed give more engine protection headroom. What it boils down to is the fact that thicker oil (more HTHS) under the same operating conditions will give larger film thickness between moving parts, and therefore more wear protection. I care less about what other use (even though I post about why viscosity might matter), but I always bump up from a recommended xW-20 to a 5W-30. No engine specifying a xW-20 is going to suffer any consequences whatsoever from using a 5W-30 ... except maybe 0.01 MPG less fuel mileage. Not worth it to me to sacrifice more engine protection for a tiny sliver of fuel mileage that would be negated for the whole tank of gas by one high throttle row through the gears from a stop light, lol.

If you were using your engine hard, would you rather possibly be on the edge of losing full protection if you got into a surprise severe driving condition, or would you rather have some protection headroom and insurance? That's basically why people will run one viscosity grade higher than what the auto makers recommendation which is primarily driven by CAFE to sacrifice some possible engine wear for a small gain in fuel mileage.

I don't completely disagree, but I would also reverse that as a few CST's of VII's are not going to make or break an engine failure from poor design. There are probably 1000's of Toyota 3.0L engines from the late 90's to early 2000's that suffered serious losses in horsepower and oil burning from a poor cooling design that used 5W-30 as the recommended oil. Many owners probably even used 10W-30, who knows? Some were even catastrophic failures Toyota covered under its 'stealth warranty'. Unless one used a full syn 5W-30 the oil still cooked on hotspots MOFT be ****ed! And even the full syn risked the worst of both worlds: a slightly compromised engine turned into an oil burner that wasn't serviced under warranty...

 

[ZeeOSix]

I don't completely disagree, but I would also reverse that as a few CST's of VII's are not going to make or break an engine failure from poor design. There are probably 1000's of Toyota 3.0L engines from the late 90's to early 2000's that suffered serious losses in horsepower and oil burning that used 5W-30 as the recommended oil. Many owners probably even used 10W-30, who knows? Some were even catastrophic failures Toyota covered under its 'stealth warranty'. Unless one used a full syn 5W-30 the oil still cooked on hotspots MOFT be ****ed! And even the full syn risked the worst of both worlds, a slightly compromised engine turned into an oil burner that wasn't serviced under warranty...

I have never claimed in any discussion that any oil or change in viscosity is going to "fix" a mechanical design issue. Think we all pretty much agree there.

Also, concerning the late 90s and early 2000s, I'd say the oils back then were not as robust as they are today. Could be many people who had issues were partly caused by how they treated and maintained those vehicles. We all know that oil burning can be caused by the rings sticking, which is typically an oil and maintenance problem, not an engine design problem - but sometime not, like some Toyota engines. That can still happen today if someone really abuses the lack of maintenance oil changes - and some engines are more sensitive to lack of maintenance than other - ie, Toyota ring sticking on some engines - which could be considered a "design problem".

But the fact remains that viscosity does make a difference on how moving parts stay separated. When separation breaks down, the rubbing and wear increases. Also, the oils today most likely have better AF/AW additives, which is the only next level of protection (the "film strength") against wear when the viscosity fails to keep parts separated enough.

 

[kschachn]

I don't completely disagree, but I would also reverse that as a few CST's of VII's are not going to make or break an engine failure from poor design. There are probably 1000's of Toyota 3.0L engines from the late 90's to early 2000's that suffered serious losses in horsepower and oil burning from a poor cooling design that used 5W-30 as the recommended oil. Many owners probably even used 10W-30, who knows?

What difference would the winter rating make in terms of wear within the same grade?

 

[easym]

I just stick by the book. And not me personally but a co-worker of mine pulls a 20’ plus boat trailer and landscaping trailer with a tundra that he runs 0w20. My fathers friend has a f150 ecoboost pulls a car and horse trailer runs 5w20 I’m sure there’s a large majority of people not stepping up oil weights but as the saying goes different strokes for different folks.

I would trust Toyota engineers more than the Chrysler engineers. For most people it's better to stick with manufacturer's recommendations but Chrysler had 10 years to perfect the Pentastar but still they haven't made Pentastar flawless. When GM and Chrysler changed to 0W20, there were engine failures, may be it's due to AFM/MDS but in pentastar there is no MDS but the hypothesis here is people who used 5w30 and frequent OCI in pentastar had less rocker failures.

 

[Schandyman]

What difference would the winter rating make in terms of wear within the same grade?

Because people think thicker is better

 

[Schandyman]

That magical 10 must be better 2x better than 5w.

 

[kschachn]

Because people think thicker is better

Mhm. Guess it’s a response I’d expect.

 

[1BadManVan]

Just curious, to those of us with the newer designed PUG motor that was designed and calls for 0w20 worldwide, are you still thinking we would be going to a thicker oil for it?

 

[CarbonSteel]

Just curious, to those of us with the newer designed PUG motor that was designed and calls for 0w20 worldwide, are you still thinking we would be going to a thicker oil for it?

We as in the owners or we as in Stellantis?

 

[Jackson_Slugger]

What difference would the winter rating make in terms of wear within the same grade?

Is the winter rating the only difference between a 5W-30 and a 10W-30? Really?

 

[1BadManVan]

We as in the owners or we as in Stellantis?

The owners of these motors. From my research on here, these were redesigned around 0w20, one of the very few motors out there that calls for 0w20 worldwide, even in extreme climates

 

[Jackson_Slugger]

I would trust Toyota engineers more than the Chrysler engineers. For most people it's better to stick with manufacturer's recommendations but Chrysler had 10 years to perfect the Pentastar but still they haven't made Pentastar flawless. When GM and Chrysler changed to 0W20, there were engine failures, may be it's due to AFM/MDS but in pentastar there is no MDS but the hypothesis here is people who used 5w30 and frequent OCI in pentastar had less rocker failures.

What is your source for these GM/FCA "engine failures"?

 

[Jackson_Slugger]

That magical 10 must be better 2x better than 5w.

The reason I mentioned it is because Toyota approved both weights for that year...

 

[ZeeOSix]

Next thing we will hear is "W" doesn't stand for "Winter".