Originally Posted By: Jeffs2006EvoIX
Well I know the HTHS has to be at lease 3.5 since it meets certain Euro specs. It has its own page dedicated here on BITOG its so popular. haha. I have emailed M1 about using their HM oil in my low mileage car, they have not responded yet. I am just concerned about the extra additves that are in the HM to clean the engine from sludge of high miles with dino oil, and the seal additives. I am not sure that makes a difference or not. I just don't want to add the HM and find out it has adverse affects??
From my understanding as well, the M1 HM is PAO not Group 3 is it safe to say that? Or do we really not know? So far the M1 HM really seems tough to beat for my application. Again, the Redline is awesome, but ordering it would be a hassle, the $10 per qt and shady looking VOA's and UOA's kinda make me think twice on that stuff.
Thoughts?
The higher detergency of HM won't hurt anything. If there is no sludge to clean, there is no sludge to clean. Mobil does recommend that the first change with HM be a short one, but since you're only going 3k miles, it's probably short enough.
We really don't know the proportions of base stock groups in any of these oils. I'm basing my conclusions of Syntec based on things that were true 15 years ago, and not necessarily so today. They probably all have some content from different base stock groups. The proportions of which, they ain't tellin', so informed decisions aren't possible. Just educated guesswork.
Basically, I've talked myself into M1 HM for future oil changes, in preference to basic M1.