Switch to High Mileage Oil or No?

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4,112
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WA
Originally Posted by SubieRubyRoo
Originally Posted by billt460
I'm beginning to think "High Mileage" oil is somewhat of a snake oil. I'll only add that I would love to be proven wrong about this.
MolaKule has gone on the record stating that high mileage oils generally have a more robust antioxidant package than a non-hi-mi version, along with other "good" stuff (usually extra detergents and seal conditioners). He even said it may be preferable to run high-mileage oil from day one to maximize its benefits; and considering that 99% of the time, the high-mileage version is the same cost as the "regular" version, what downside is there?
+1 Ppl think a HiMi is some exotic formula but in fact it's more similar to the plain formula than it is different. As you pointed out it's more "robust"..more or better seal conditioning agents, usually higher ppm total of AW additives and dispersants/detergents. Some HiMi formulas even have higher than avg TBNs, presumably to combat the blow by that older engines experience. In short there is nothing in a HiMi formula that is going to grenade your engine or existing seals or as I've suggested before, oil mfgs a) wouldn't be recommending it for even new engines and b) would have to slap a disclaimer on the bottle saying "Do Not Use Unless Your Seals Are Leaking"...... and fwiw, asking a seal conditioner to stop an already blown out seal is a tall order which it may or may not be able to do depending on the size of the leak..they (sca's) work best prophylactically - preventing the seal from becoming dried out and cracking to begin with. One might ask, "how does a seal become dried out in an engine"?.. indeed a good question, over time varnish and sludge can coat a seal preventing it from being exposed to the lubricants conditioners..in time that seal can shrink and crack..so the detergents in a HiMi are designed to clean out that sludge and varnish so the leaking seal can once again be exposed to the SCA's.. this process can take some time; several thousand miles.
 
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4,112
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WA
Originally Posted by Mackelroy
My experience, don't use seal agents unless necessary and willing to take on the risk. ..
What if I told you that all finished lubes have seal conditioners?🤔
 
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6,522
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Wet side WA
Originally Posted by Mad_Hatter
Originally Posted by Mackelroy
My experience, don't use seal agents unless necessary and willing to take on the risk. ..
What if I told you that all finished lubes have seal conditioners?🤔
LOL now was that nice you just rained on someone's TGIF doom a glum day. crackmeup
 
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4,112
Location
WA
Originally Posted by JohnnyJohnson
Originally Posted by Mad_Hatter
What if I told you that all finished lubes have seal conditioners?🤔
LOL now was that nice you just rained on someone's TGIF doom a glum day. crackmeup
shrug coffee
 
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6,748
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Lake Havasu City, Arizona
Originally Posted by Mad_Hatter
One might ask, "how does a seal become dried out in an engine"?.. indeed a good question, over time varnish and sludge can coat a seal preventing it from being exposed to the lubricants conditioners. in time that seal can shrink and crack..so the detergents in a HiMi are designed to clean out that sludge and varnish so the leaking seal can once again be exposed to the SCA's.. this process can take some time; several thousand miles.
What if you changed oil and filter religiously to prevent sludge buildup? There isn't anything for HM oil to, "clean up". No sludge or varnish, but yet you still have a leak. Now what? The HM oil isn't going to accomplish anything, because you don't have the crap in your engine the stuff is supposed to remove.
 
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WA
Originally Posted by billt460
What if you changed oil and filter religiously to prevent sludge buildup? There isn't anything for HM oil to, "clean up". No sludge or varnish, but yet you still have a leak. Now what? The HM oil isn't going to accomplish anything, because you don't have the crap in your engine the stuff is supposed to remove.
Changing the oil and filter religiously doesn't guarantee you won't have any sludge or varnish. Sludge and varnish is but one concern, warping of metal like on valve covers can cause failure of the oil seal system. Pitting (due to acids) or burrs on the crankshaft can wear on the softer seals causing them to leak. Engines that run hotter than normal can also decrease the mtbf of a seal. Point is, there are a number of reasons why seals fail...I mentioned just one reason, that a HiMi formula can help with. Whether you choose to accept that it's a "thing" is up to you but it doesn't change the fact that it's a legitimate cause of seal failure. And fwiw, the higher levels of AW additives found in a HiMi formula is reason enough for many, like myself, to use it. But hey.. this is America.. don't let me stop you from doing you.... *my post was not meant to be an exhaustive review of oil seal failures. Feel free to PM if you want to discuss further.
 
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Messages
234
Location
Texas
It won't be a problem. Try 5w30 in that F150 and use the same for your wife's car. Simplify your life and don't look back. You could use supertech if you wanted, or any SN+ oil should do nicely for both vehicles.
 
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pa
HM oils are said to cut leakage as it did on my aunts 99 jeep cherokee + they generally are on the higher end of their viscosity spread. running most any cheaper group III synthetic @ $5 + or - a qt in 5 qt containers 5-30 would be beneficial, if you see leakage use a 5-30 HM fake synthetic!!
 
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Location
Missouri
Thread starter
Originally Posted by Tdog02
It won't be a problem. Try 5w30 in that F150 and use the same for your wife's car. Simplify your life and don't look back. You could use supertech if you wanted, or any SN+ oil should do nicely for both vehicles.
I would if I didn't have a Lifetime Powertrain Warranty on the truck. Have to be by the book with it for claims (which I've already had to use once frown ) Sure, they'd have to prove it was the cause and what not, but I'd rather not give them any leverage to deny a claim or void the warranty.
 
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4,112
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WA
Originally Posted by mailman74
Why no Amsoil on the high mile bandwagon.
If I had to guess, because a) they use a fair amount of esters already to prevent their base oil from drying up seals, b) their AW add pack is already stout c) POA/POE base oil has a high solvency IIRC, so it already does a pretty good job of keeping an engine clean. In short, a HiMi formula would not be that much different from their pre-existing formula.
 
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26
Location
Missouri
Thread starter
Originally Posted by Mad_Hatter
Originally Posted by mailman74
Why no Amsoil on the high mile bandwagon.
If I had to guess, because a) they use a fair amount of esters already to prevent their base oil from drying up seals, b) their AW add pack is already stout c) POA/POE base oil has a high solvency IIRC, so it already does a pretty good job of keeping an engine clean. In short, a HiMi formula would not be that much different from their pre-existing formula.
Does that list apply strictly to their Sig Series formulation or do their XL and OE formulations also have the same characteristics you listed? I've thought about checking into those, but I do not really know how to find out about how the XL and OE formulations compare to say M1 EP, M1 AP, MaxLife HM, or other full synthetics I could find at WM.
 
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67
Location
FL
It looks like aside from price, nobody can give you a legitimate downside to using HiMi oil. I'm certainly not familiar with oil to the level most of these guys are, but from what I'm reading, I don't know why you wouldn't try HiMi. Again, unless a small change in price is a concern. In my my experience it's usually the same price anyways, or at least extremely similar. I use HM in all 4 of the vehicles we have. Mileage on them ranges from 66k-240k
 
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4,112
Location
WA
Originally Posted by Blake1107
Originally Posted by Mad_Hatter
Originally Posted by mailman74
Why no Amsoil on the high mile bandwagon.
If I had to guess, because a) they use a fair amount of esters already to prevent their base oil from drying up seals, b) their AW add pack is already stout c) POA/POE base oil has a high solvency IIRC, so it already does a pretty good job of keeping an engine clean. In short, a HiMi formula would not be that much different from their pre-existing formula.
Does that list apply strictly to their Sig Series formulation or do their XL and OE formulations also have the same characteristics you listed? I've thought about checking into those, but I do not really know how to find out about how the XL and OE formulations compare to say M1 EP, M1 AP, MaxLife HM, or other full synthetics I could find at WM.
Dunno...I believe they use a majority PAO w/POE ester???..I think Redline does as well...anywho, there's an Amsoil rep ("Pablo") for the board isn't there?.. and I think there's a Amsoil sticky on the main forum page. Message him and see what he says.. In the interim here's some BITOG reading... https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4747911/all/Honest_Amsoil_Question https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=890924 From this 👇dealers page: "AMSOIL's Premium Lubricants are made up primarily of Group IV PAO base oils (with some Group V Esters)" https://www.selectsynthetics.com/base-oil-groups.html
 
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1,186
Location
California
Hitting a certain number on the odometer is not a good reason to start using high mileage oil. HM oils are designed to address issues that eventually happen to nearly every engine as the miles accumulate: noisy on startup, oil consumption, seeping/leaking engine seals, etc. If your engine is showing these symptoms, a HM oil is likely to help. But if your engine is still running fine on non-HM oil and shows no symptoms, just keep using whatever has been working for you. My Tacoma has 156,000 miles and I have no intention to use HM oil until there is good reason.
 
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