"Seal swellers" in HM oil

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Hi,

I have a question. If one stops using a HM oil, does the rubber go back to the original size or does it go back to a smaller size?

Thanks,

-kehyler
 
Originally Posted by csandste
No. It's a conditioner not a sweller.


So you mean that it doesn't shrink afterwards?
 
Originally Posted by csandste
Right. I switch back and forth, depending on price, without incident.



This I just bought two Jugs of PUP HM from WM for $14 each without rebate.

Yes because it was $8 cheaper!
 
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Unless somebody has proof that I've never been able to find.
Nobody really knows for sure what HM oil really does or doesn't do. I'm of the opinion that HM oil is just another marketing plan to get buyers to pay for something they don't really need. I'll admit I've been tempted to try it, but never have because I've logged a lot of miles on regular Dino and synthetic oils that were not HM.
 
I know Mobil 1 HM oil is higher viscosity and does seem to help if you have small leaks. Never had luck with Valvoline Maxlife that so many others brag about. Haven't used many other HM oils. About to try some STP - autozone brand 10W30 in my 2003 Mercury Sable that i got on clearance a few months back.
 
There ya go boys and girls
My read is as long as your doing regular OC's and your engine is in good to normal condition.
HM is a waste of money
No matter how many miles your engine has !!ðŸ‘
 
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Super Tech Full Synthetic SAE 10W-30 Motor Oil vs. Amazon Basics Full Synthetic are both made by Warren Oil. Are they the same product?
 
Originally Posted by kstanf150
Unless somebody has proof that I've never been able to find.
Nobody really knows for sure what HM oil really does or doesn't do. I'm of the opinion that HM oil is just another marketing plan to get buyers to pay for something they don't really need. I'll admit I've been tempted to try it, but never have because I've logged a lot of miles on regular Dino and synthetic oils that were not HM.



Most HM oils have a slightly higher percentage of seal conditioners and in most cases, the basic viscosity is slightly higher as well.

Most seals are elastomers,and seal conditioning chemistry replaces some of elatomer molecules that have been lost to wear and heat.

Are HM oils another avenue of income for oil manf., of course, but they also help high mileage engines in various ways.
 
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But, to what degree of help???
That's the question ?
No data I've found can compare a new seal vs an old seal that's been brought back to life with HM oil.

So until I see real data and proof
HM oil is just marketing
 
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No it's not. Mobil1 HM oils are the same price at WM as the vanilla M1 oils. HTHS and V@100 are on the "thick" side which is why I use them. Also has stopped oil seal seeps in my old junks. So there's "some" proof of usage.
 
Maybe HM oils had a use back in the day of gaskets and such. Today's engines use more sealants instead.

In my over 40 years of driving and changing oil I have never used a HM oil.
 
Originally Posted by PimTac
Maybe HM oils had a use back in the day of gaskets and such. Today's engines use more sealants instead.

In my over 40 years of driving and changing oil I have never used a HM oil.

Except valve seals that start seeping oil down the valve stem.
 
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