High mileage oil just contains seal swellers?

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Years ago, i saw this was supposed to be the case, was it true? and is it still true?

Example, the manufacturers seem to consider anything over 75k miles as high mileage, any reason to use it when over that mileage?
 
This was never the case.

HM oils contain a very small but increased level of detergent, AW, and seal swell chemistries over the standard formulation (within the same brand). It may also have a slight increase in viscosity (0.25 to 0.5 cSt ) over the standard formulation (within the same brand).
 
Valvoline Synthetic Maxlife according to the site has slight increase in viscosity, antiwear ingredients, seal conditioner etc. On frequently asked questions they claim that it is a stronger formula compared to Advance formula so you can use it with low mileage engine.
 
This was never the case.

HM oils contain a very small but increased level of detergent, AW, and seal swell chemistries over the standard formulation (within the same brand). It may also have a slight increase in viscosity (0.25 to 0.5 cSt ) over the standard formulation (within the same brand).

So what happens if you use a high mileage oil in a brand new engine? What if you go back to a regular motor oil after one or more oil changes with the high mileage oil? I've been wondering this for a long time, and probably others as well. Thank you.
 
Whether or not it increases seal conditioners or any other part of the chemistry, as long as it's an API SP oil (for example) it must fall within all parameters of that specification before being labeled API SP. In other words, the API limits how much of any ingredient may be used. Just like oils meeting viscosity. There's a viscosuty range for every "weight". There are thicker and thinner variants of say a 5W-30 depending on manufacturer and often times within a manufacturer's portfolio of products.
 
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What is the greater or lesser part of zero!

Thanks for the riddle.

Whether or not it increases seal conditioners or any other part of the chemistry, as long as it's an API SP oil (for example) it must fall within all parameters of that specification before being labeled API SP. In other words, the API limits how much of any ingredient may be used. Just like oils meeting viscosity. There's a viscosuty range for every "weight". There are thicker and thinner variants of say a 5W-30 depending on manufacturer and often times within a manufacturer's portfolio of products.

All I wanted to know is if it can mess up the seals in a new engine. If I'd known for sure I wouldn't ask. Thank you for answering this for me, it makes sense.
 
I did notice that Castrol edge showed about 0.5 increase in viscosity of their 5w20 for the high mileage version, but only the GF6 product, GF5 was the same as non high mileage.
 
Thanks for the riddle.



All I wanted to know is if it can mess up the seals in a new engine. If I'd known for sure I wouldn't ask. Thank you for answering this for me, it makes sense.
Valvoline uses seal conditioner so no damages in New engine and even has a 300k engine warranty
 
..All I wanted to know is if it can mess up the seals in a new engine. If I'd known for sure I wouldn't ask. Thank you for answering this for me, it makes sense.

The answer is no.

Conditioning seals refers to the following actions:

1) Increasing seal pliability due to molecular replacement of the Seal's elastomer
2) Seal cleaning,

Nothing can repair or rebuild a failed or damaged seal.

Since about 1974, mineral and synthetic formulations have solved the seal "shrink-swell" problem.

HM oils can be used in new engines. My take is use them in new engines only if the cost is economically feasable.
 
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The answer is no.

Conditioning seals refers to the following actions:

1) Increasing seal pliability due to molecular replacement of Seal's elastomer
2) Seal cleaning,

Nothing can repair or rebuild a failed or damaged seal.

Since about 1974, mineral and synthetic formulations have solved the seal "shrink-swell" problem.

HM oils can be used in new engines. My take is use them in new engines only if the cost is economically feasable.

This should be a sticky!
 
So, if the HM oils have "more of the good stuff", so to say, then what is the trade-off as compared to non-HM oils? I mean - if they are offered at the same price, then there must be a trade-off... Doubt the oil blenders just sprinkle more stuff into the mixture without taking something out to compensate for the extra cost.
 
So, if the HM oils have "more of the good stuff", so to say, then what is the trade-off as compared to non-HM oils? I mean - if they are offered at the same price, then there must be a trade-off... Doubt the oil blenders just sprinkle more stuff into the mixture without taking something out to compensate for the extra cost.

It seems like motor oils within the same brand are priced identically with very little variation within the same brand. Oil companies made this work for them by leveling the pricing. At Walmart Mobil 1 FS 0W-40 is priced the same as the rest of Vanilla Mobil 1 oils, so are the HM oils within that line. EP oils are $2 more, and HM EP is the same price as regular EP. I think that Pennzoil an Valvoline get less space at Walmart than than Castrol and Mobil 1 so the selection is more limited with those two brands. That would explain why PUP is so hard to get.

As to the trade-off when it comes to regular vs. HM oils, I think it's bad marketing on one hand, and the other is that not all HM oils, probably most of them have various certifications like Dexos for example. It's mostly marketing though. My only concern with HM oils was that they might mess up the seals on new cars, but that was answered for me. I guess that if you want the thickest xW-20 or xW-30 oils with the most detergents and AW additives your only choice is a HM oil. And I believe they're marketed like this because otherwise everyone would most likely just buy the HM oil leaving the rest behind. Again, it's marketing and it works wonders for taking up shelf space and as far as we're concerned, we'll never pick up that HM jug unless we drive a beater.
 
So what happens if you use a high mileage oil in a brand new engine? What if you go back to a regular motor oil after one or more oil changes with the high mileage oil? I've been wondering this for a long time, and probably others as well. Thank you.
Nothing happens. IIRC the oil companies have answered this question many times, as well as Bitog members. If you think it will prolong the life of your engine, go for it.
 
I've often believed additives are a balancing act. You need enough to accomplish it's function. Any in excess of that would appear to me to just add to the potential for more deposits.
 
So are we saying that, for the most part at least, high mileage oils are no worse for a new or non-high-mileage engine than regular oil?

Are we saying that some of the HM oils are a little thicker in the viscosity range of the rating?

And lastly, saying that they can (do?) contain a little more additives to help with wear?
 
So are we saying that, for the most part at least, high mileage oils are no worse for a new or non-high-mileage engine than regular oil?

Are we saying that some of the HM oils are a little thicker in the viscosity range of the rating?

And lastly, saying that they can (do?) contain a little more additives to help with wear?
That is correct
 
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