Originally Posted by Dave9
That is misleading. If you have a bad seal, that is a legitimate use of a hi-mi oil with seal swellers.
If you don't have a bad seal, or every other seal that wasn't bad, is degraded from seal swellers and wears faster from being introduced to them. Seal swellers will make a good seal wear out faster. This bears repeating. Seal sweller will make a good seal wear out faster.
This is a false statement. Show me one bit of scientific evidence, not anecdotal, that supports your claim.
Use of a HiMi oil isn't going to degrade a good engine seal. Seal conditioning agents (SCA's) don't attack and breakdown natural and synthetic rubbers like a solvent might. Seal conditioners act much in the same way a salve for your skin does, it
restores elasticity and to a very small degree volume. The effect on a good seal is to keep it from drying out. Fact is, most every major oil mfg produces a HiMi formula and recommends use of their HiMi formulas in engines of all ages, including new(er) engines. See attachments.
Like I said, I have nearly 170k on the original valve stem seals and main seals with no leaks/burning, and I regularly go back and forth between HiMi and vanilla. I guess I'm waiting for this "degradation" effect to which you speak of?🤔 So if you do know something about seal conditioners that ExxonMobil or Chevron doesn't, please share. (and fwiw many of these companies, like Chevron & XOM, have guarantees warrantying against any lubricant related failures)
Valvoline MaxLife..
Mobil 1...
Mobil 1 Link
Chevron Havoline HiMi...(will not void mfg warranty)