Question: What is molybdenum’s real role?

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SubieRubyRoo

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I have zero doubt that oil will work great in your Sooob.
Uhhh- it’s in my ‘19 F150 3.5EB, with an S&B intake, AMS turbo intake tubes, AMS turbo adapters, a 5 Star Tuning E30 tune, and a CV Fab Titan 2 intercooler on the way.

The Impreza won’t get HPL at this point because I’m worried the AN/Ester combination may be enough to take my already-oil-weeping original HGs and hasten their demise. Next spring I’m planning on putting some SixStar MLS on it and then I’ll be fine putting HPL in it 👍🏻
 

TiGeo

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Uhhh- it’s in my ‘19 F150 3.5EB, with an S&B intake, AMS turbo intake tubes, AMS turbo adapters, a 5 Star Tuning E30 tune, and a CV Fab Titan 2 intercooler on the way.

The Impreza won’t get HPL at this point because I’m worried the AN/Ester combination may be enough to take my already-oil-weeping original HGs and hasten their demise. Next spring I’m planning on putting some SixStar MLS on it and then I’ll be fine putting HPL in it 👍🏻
Ah sorry, what will that Ford do in the 1/4?
 

SubieRubyRoo

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Ah sorry, what will that Ford do in the 1/4?
Haven’t had a chance to take it to the track just yet, but it has done a ~4.65 0-60 and ~10.65 0-100. I’m guessing that will equate to around a mid-12 around 110? If a couple things fall into place, the truck will also be getting some Precision turbos & CRP manifolds, a 3” stainless downpipe/cats, an XDI +60 HPFP, and a 440lph in-tank which would allow “full” E85 race fuel and corresponding tune. 5 Star’s shop truck was outfitted similarly and topped 700rwhp and lived well over 60k miles before being sold, so that’s definitely a possibility

My ‘09 GT GT ran a [email protected] with nothing more than a Diablo Predator 91 tune, and I have no doubts the truck is faster as it sits. One issue is my local dragstrip has a headwind out of the south probably 75% of the time; it’s frustrating.
 

TiGeo

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Haven’t had a chance to take it to the track just yet, but it has done a ~4.65 0-60 and ~10.65 0-100. I’m guessing that will equate to around a mid-12 around 110? If a couple things fall into place, the truck will also be getting some Precision turbos & CRP manifolds, a 3” stainless downpipe/cats, an XDI +60 HPFP, and a 440lph in-tank which would allow “full” E85 race fuel and corresponding tune. 5 Star’s shop truck was outfitted similarly and topped 700rwhp and lived well over 60k miles before being sold, so that’s definitely a possibility

My ‘09 GT GT ran a [email protected] with nothing more than a Diablo Predator 91 tune, and I have no doubts the truck is faster as it sits. One issue is my local dragstrip has a headwind out of the south probably 75% of the time; it’s frustrating.
That's fast considering how heavy those are. My best in my Sportwagen using Dragy was 3.91 0-60 and 12.10/113.4 1/4 mile. It was really cold at sealevel for a huge negative DA which really helps a small turbo. At the track, at least the conditions are equal for eveyrone but if you are chasing solo times, yeah that sucks. Get a Dragy and find a road.....
 

SubieRubyRoo

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That's fast considering how heavy those are. My best in my Sportwagen using Dragy was 3.91 0-60 and 12.10/113.4 1/4 mile. It was really cold at sealevel for a huge negative DA which really helps a small turbo. At the track, at least the conditions are equal for eveyrone but if you are chasing solo times, yeah that sucks. Get a Dragy and find a road.....
One of the things that actually hinders the 60-100 time flat out is the 4-5-6 change; the ratios are so close that 5th gear is literally no more than 1-1.5 seconds, which doesn’t make sense with 600+ ft-lbs on tap… my truck only has 3.55s as well which equates to [email protected] in 10th
 
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I've asked this before a really long time ago (I think?), but is the sediment-like substance everyone keeps finding at the bottom of the Pz jugs MoS2 type moly falling out of suspension, while the MoDTC type moly found in M1 staying better in suspension?

Reason of my suspicion is that MoS2 added from the can as posted by many respected members here eventually settles onto the bottom of your engine's oil pan.
Reason of my suspicion is that MoS2 added from the can as posted by many respected members here eventually settles onto the bottom of your engine's oil pan.

Used it and never once did it settle. My understanding was that the settling out by Sopus oil didn't effect the integrity. On the solid lubrication fears of Mos2, it's often used at motorsport events where high RPM is common. I do run our vehicles on a regular basis so the fear of it possibly settling out is nil.
 
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Reason of my suspicion is that MoS2 added from the can as posted by many respected members here eventually settles onto the bottom of your engine's oil pan.

Used it and never once did it settle. My understanding was that the settling out by Sopus oil didn't effect the integrity. On the solid lubrication fears of Mos2, it's often used at motorsport events where high RPM is common. I do run our vehicles on a regular basis so the fear of it possibly settling out is nil.
The Pz mystery will probably always remain the ultimate motor oil urban legend! (y)
 
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Friction does not equal wear. Even without friction an engine wears. Abrasive wear, caused by friction isn't the only wear mechanism. But even when we only look at abrasive wear there's no correlation between friction and wear. Phosphate glass has a high friction coefficient (the stuff that zddp lays down) but it wears instead of the metal it's protecting.

MoS2 is very low on the Mohs hardness scale, it's amongst the softest substances around. Quite like graphite, the stuff that pencils are made of and that has trouble tearing up paper....

MoDTC puts another low friction layer on top of the anti-wear layer, it's not going to reduce wear that's not happening anyway but it can reduce friction.
What? If there is no friction, there will be no wear. Wear exists due to friction. If parts do not touch, there is no wear.. Please explain.
 

ZeeOSix

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there will be no abrasive wear, but there can be chemical wear (acids)
There is always abrasive wear going on due to the engine components that run in mixed and boundry lubrication. Where do you think the stuff caught on a magnetic drain plug comes from?
 
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My understanding is that moly is a consumable last chance defense. Some time ago Mobil-1 greatly decreased the moly content of formerly much loved 15W-50. Then owners of high lift hot rods w/o roller cams started having failures. High forces on high lift cams consumed the moly. Mobil-1 had to eat crow, restored the moly content, but reputation lost. Those who ran very short drain intervals did not experience wear but those going as long as 3000 miles had problems.

Similar situation: motorcycles use a one-way sprague clutch for the electric starter. Roller high pressure on shaft. Much fear of "energy saving" oils due to the starter failing to bite. Word of mouth only hears "clutch" when repeated so the starter part is lost in folklore tellings. Genuine Honda motorcycle oils used to prominently feature moly, owners manuals used to specify moly oils. Then I think it was the then-new GL1500 which changed things. Owners were flooding dealers with calls from Dairy Queens, "on the way home from our first oil change my motorcycle won't start, it spins but no hit". The factory first fill was a non-moly oil but all the dealers had was Genuine Honda moly oil. Engine starts fine when cold but warm moly kept the sprague clutch from biting. Honda had to specify use of non-Honda oil until they could get a non-moly product to dealers.

Oddly many motorcycle electric starters worked fine with moly oil, but others did not.
 
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My understanding is that moly is a consumable last chance defense. Some time ago Mobil-1 greatly decreased the moly content of formerly much loved 15W-50. Then owners of high lift hot rods w/o roller cams started having failures. High forces on high lift cams consumed the moly. Mobil-1 had to eat crow, restored the moly content, but reputation lost. Those who ran very short drain intervals did not experience wear but those going as long as 3000 miles had problems.
Consumed the moly?

And when did this happen?
 
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there will be no abrasive wear, but there can be chemical wear (acids)
Being here to learn I give you what I know. On the Stribeck curve EP additives are used on the boundary zone and FM additives are used in the mixed zone. The boundary zone has adhesive and corrosive wear. I am thinking because some oil additives are heat activated they are EP additives. But would you say moly is a EP due to the sulphur, or a FM?
 
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OVERKILL

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My understanding is that moly is a consumable last chance defense. Some time ago Mobil-1 greatly decreased the moly content of formerly much loved 15W-50. Then owners of high lift hot rods w/o roller cams started having failures. High forces on high lift cams consumed the moly. Mobil-1 had to eat crow, restored the moly content, but reputation lost. Those who ran very short drain intervals did not experience wear but those going as long as 3000 miles had problems.

Similar situation: motorcycles use a one-way sprague clutch for the electric starter. Roller high pressure on shaft. Much fear of "energy saving" oils due to the starter failing to bite. Word of mouth only hears "clutch" when repeated so the starter part is lost in folklore tellings. Genuine Honda motorcycle oils used to prominently feature moly, owners manuals used to specify moly oils. Then I think it was the then-new GL1500 which changed things. Owners were flooding dealers with calls from Dairy Queens, "on the way home from our first oil change my motorcycle won't start, it spins but no hit". The factory first fill was a non-moly oil but all the dealers had was Genuine Honda moly oil. Engine starts fine when cold but warm moly kept the sprague clutch from biting. Honda had to specify use of non-Honda oil until they could get a non-moly product to dealers.

Oddly many motorcycle electric starters worked fine with moly oil, but others did not.

You sound like you are confusing moly with phosphorous. Moly does provide some AW function, but its mostly a friction modifier, though it has some synergies with ZDDP. Phosphorous (provided via ZDDP) creates the AW "glass" that's sacrificed in what would otherwise be metal-on-metal situations. Yes, moly where it shouldn't be (on clutches) could cause issues in theory.

Also, the rash of cam failures was, in large part, due to poor quality imported cores with improper hardening as that industry was sent overseas once the industry shifted to roller and FT sticks became niche.

I have no recollection of the Mobil saga you've shared, but I do remember oils being blamed for camshaft failures more broadly, in FT applications. As with many things, this was not as simple as perceived. There were several factors influencing how this played out, with the quality issue (noted above) as well as the legitimate reduction in phosphorous, mandated by the API, with the introduction of API SM. However, grades that were not "resource conserving" were not impacted by this restriction, so xW-40 and xW-50 grades for example, were never required to make the reduction. Lifter quality was also an issue.
 
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Being here to learn I give you what I know. On the Stribeck curve EP additives are used on the boundary zone and FM additives are used in the mixed zone. The boundary zone has adhesive and corrosive wear. I am thinking because some oil additives are heat activated they are EP additives. But would you say moly is a EP due to the sulphur, or a FM?

ZDDP contains sulfur aswell, doesn't make that an EP additive. It is also heat activated. I, not being a tribologist consider MoS1 first a friction modifier, as I would graphite. Calcium sulfonate on the other hand....
 
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