Originally Posted By: Danh
Originally Posted By: volk06
Originally Posted By: Danh
Let's try this: mass market synthetic oils (Pennzoil, Valvoline, Castrol, Mobil, Kendall, etc) are all pretty much the same. Pennzoil Ultra and Amsoil have different, and some would say better, base stocks, but let's stick with the mass market oils for the time being.
These oils are pretty much the same in that their base oils are largely extra-refined crude oil and additive packs are similar. If you want to see how similar, go to the PQIA's website and look at their recent comparison of synthetics. There are variances: Valvoline tends to use sodium, some Mobil and Castrol products uses titanium, but they aren't that different.
So how is Mobil1 HM different from the rest? First, it likely contains more seal conditioners than the others to help with leaks. Second, it contains more phosphorous (in the form of ZDDP, I think), which is an anti-wear additive. You will note that M1 HM is rated API SL, not the current SN of others. This is because of the extra phosphorous. M1 HM also claims to clean very well - what component makIes this possible, I don't know. M1 HM in a 5w30 is on the "thicker" side of the spectrum, to minimize oil consumption. Curiously, the 5w20 is on the "thinner" side. Go figure.
So, what oils compare to M1 HM? Accepting it isn't all that different from others to start, Valvoline MaxLife full synthetic seems comparable. Many of the blend HM oils have extra seal conditioners, but then they aren't full syns. Again, while M1 HM is a little different than most syns, these differences on on the margins: it's not a magic elixir. It's also priced the same as regular M1 at WalMart if that tells you anything.
A few things to add. Mobil only uses titanium in the mobil super line, not the mobil 1 line up. Castrol only uses titanium in Edge with Ti, edge with syntec does not use titanium. There are quite a few more differences than people think because most people just use a VOA/UOA to judge an oil which is only a small part of the picture. Most full synthetics are mostly group III like you mentioned but they also have some group IV or V depending on the oil manufacturer. M1 HM is also SL due to the Zinc and P. ZDDP is for zinc, not P.
Splitting hairs here, but ZDDP = Zinc dialkyldithioPHOSPHATE, so I thought both zinc and phosphorous were present.
Nope. Thats why all the ZDDP and P levels are different in oils. If they were the same additive.compound, all the zinc and p levels would be the same.