HIGH MILEAGE OIL VS EVERYTHING ELSE...

[geeman789]

A couple of high mileage threads got me thinking...

Don't all modern oils contain a seal conditioner / sweller? etc. Wasn't that an issue with synthetics back in the day, that they didn't have enough seal sweller / conditioners, and THAT led to leaks...?

I know most HM oils are quite a bit thicker, but how much EXTRA "stuff" do they really have...? Or is it simply a case of ...add 10 cents of additive, charge $1.00 more per quart...?

 

[gregk24]

I am curious about this too? I would HOPE todays syns have the necessary seal conditioners and what not.

 

[pbm]

I have never used HM oil but I recently acquired a few quarts of Valvoline NG High Mileage 5w20 at the Pepboys closeout.

I am hesitant to use it because I worry about the 'seal conditioners' causing seal swell which would then shrink when I go back to regular oil...Is this a concern?

How does High Mileage NG 5w20 compare with regular NG 5w20 besides the seal swellers?

 

[crazyoildude]

i like PHM mixed 50/50 with PYB it has stopped leaks for me before and those two oils mixed seem to work well.. I dont use PHM in the winter i feel its to thick.

 

[MolaKule]

Originally Posted By: geeman789
A couple of high mileage threads got me thinking...

Don't all modern oils contain a seal conditioner / sweller? etc. Wasn't that an issue with synthetics back in the day, that they didn't have enough seal sweller / conditioners, and THAT led to leaks...? ...


All modern oils contain seal conditioners that help the seals increase in volume and make them more pliable.

HM oils contain a fraction of a percent more seal conditioners.

I have yet to see or read about a modern oil or an HM oil causing any seal problems in engines that do not have damaged or worn seals.

 

[geeman789]

Originally Posted By: MolaKule
Originally Posted By: geeman789
A couple of high mileage threads got me thinking...

Don't all modern oils contain a seal conditioner / sweller? etc. Wasn't that an issue with synthetics back in the day, that they didn't have enough seal sweller / conditioners, and THAT led to leaks...? ...


All modern oils contain seal conditioners that help the seals increase in volume and make them more pliable.

HM oils contain a fraction of a percent more seal conditioners.

I have yet to see or read about a modern oil or an HM oil causing any seal problems in engines that do not have damaged or worn seals.


And how much SHOULD that fraction of a % add to the price of the oil...?

 

[dave1251]

To break that down would require disclosing propriety information. So you will never know.

 

[Garak]

Originally Posted By: geeman789
And how much SHOULD that fraction of a % add to the price of the oil...?

If you look at all the HM oils on the market, there are certain differences, and not all of them are pushing the seal conditioning, either. Some claim higher additive levels. Some note that they're a blend. Some have older API certifications (or none at all) and/or are slightly thicker within the grade. Others are fully API and ILSAC certified for brand new vehicles. So, perhaps it really does depend on a few things.

 

[Mackelroy]

From what Ive seen no, but the ones that do mention seal agents ive seen some bizarre effects, such as filter orings swelling and getting mushy and popping right out of the filter when removing. valve cover gasket leaks that weren't there before.

Now Ive heard some say, no way that doesn't happen, but take it or leave it ,I don't care. I avoid Hm oils and anything with known swellers if a have a choice and a non leaking motor, cause its Russian roulette using them.





Originally Posted By: geeman789
A couple of high mileage threads got me thinking...

Don't all modern oils contain a seal conditioner / sweller? etc. Wasn't that an issue with synthetics back in the day, that they didn't have enough seal sweller / conditioners, and THAT led to leaks...?

I know most HM oils are quite a bit thicker, but how much EXTRA "stuff" do they really have...? Or is it simply a case of ...add 10 cents of additive, charge $1.00 more per quart...?

 

[CaspianM]

I have used M1 HM in my 97 Camry V6 from 90K to 150K no issues to report. Use the same on Civic from 90 to 185k w/o any adverse effect. Excellent oil all around and just a heavier duty oil compared to its standard version.

 

[MolaKule]

Quote:
Now Ive heard some say, no way that doesn't happen, but take it or leave it ,I don't care. I avoid Hm oils and anything with known swellers if a have a choice and a non leaking motor, cause its Russian roulette using them.


Then you would have to avoid all modern oils and even the oils from about SF on.

HM oils have slightly higher treat levels of detergents/dispersants, Anti-wear, seal conditoners, and in some cases, a slightly higher base oil viscosity.

 

[Vikas]

Quote:
I have yet to see or read about a modern oil or an HM oil causing any seal problems in engines that do not have damaged or worn seals.
I know where this is going already! So if the OP uses HM oil and the seal starts leaking, you are going to tell him "the seals were already damaged or worn and HM oil did not cause them but only discovered them"!

Am I right??? I love how some people do the rationalization.

 

[MolaKule]

Carnac 1


Carnac2


Copper Clappers

 

[bigt61]

Originally Posted By: gregk24
I am curious about this too? I would HOPE todays syns have the necessary seal conditioners and what not.

Are you kidding me? So you're picturing a Mobil 1 oil engineer after 40 years snapping his fingers and saying "Oh yeah, I knew there was something we forgot!"?

 

[Garak]

Originally Posted By: Mackelroy
From what Ive seen no, but the ones that do mention seal agents ive seen some bizarre effects, such as filter orings swelling and getting mushy and popping right out of the filter when removing. valve cover gasket leaks that weren't there before.

Have you seen these effects yourself, or seen them appropriately documented? I've never seen a problem with a filter o-ring unless it was a shoddy build in the first place or put on carelessly. And valve cover leaks are not terribly uncommon in older vehicles, so blaming the HM oil is a bit backwards.

 

[Triton_330]

Well, FWIW, I guess I'll join in on the fun, lol.

All I have to add to the questioning of HM oils is:

The myth that "Once you use HM, you have to keep using it or there will be leaks" is false. At least, it's false in my case. I ran Pennzoil HM in my mother's explorer (at the time probably had about 175k miles), and then at the next change ran a non-HM oil... and no leaks. So, I don't know how much that adds to this thread, but take it for what it's worth.

 

[Rosetta]

The only thing I know about seal swellers is that they're also added in brake fluid. A synthetic rubber gets turgid when imersed in brake fluid! I know you can't mix engine oil and brake fluid, but the additive is there also.

 

[joflewbyu2]

HM oils are recommended for older vehicles with more than 75,000 miles. This is another way of getting around the epa regulations for limited phosphorus and zinc in certain weight oils. Phosphorus and zinc can shorten catalytic converter efficiency and life of the converter. The catalytic converter is protected under Federal emission warranty laws too. HM oils will offer more wear protection at the expense of the converter. Just look at the mobil 1 oil chart at the ppm of phos and zinc in the different weights.

 

[wemay]

To MolaKule and Garak's point...

Castrol GTX HM - API SN (seal and doughnut)/ILSAC GF-5

Valvoline Maxlife - API SN (seal and doughnut)/ILSAC GF-5 (Valvoline Lube in my area sells it as their synthetic blend choice)

Both perfectly safe for newer vehicles and their catalytic converters according to the approvals on the bottle. Not sure if any other brands have these approvals.

 

[Garak]

Up here, our Mobil Super 2000 is a high mileage oil, also SN/GF-5 rated.