Originally Posted By: crazycrak
how are they about controlling leaks do the actually restore seals? or is that just a sales pitch
Erm...
No one is even sure that the oil has more seal conditioners. Folks have asked Mobil point blank, and received only the standard corporate bee ess.
OTOH, there are several testimonials floating around here suggesting that M1 (and other MH oils) actually can reduce seal leakage.
My own experience, with a leaky distributor seal, has been mixed. Since switching to M1HM 10W30, the seepage has slowed somewhat, but is far from cured. YMMV!
It can't hurt to try it, there's no way it will hurt the car.
In addition to the Zinc and Moly, both flavors of M1HM have a big swig of Boron, presumably integrated into an anti-wear additive.