Is high moly still a thing ? seen a post somewhere online that the John Deere 15W-40 is the best oil for diesel engines you can get in Australia because it has high moly content, is this true or high moly does not automatically make an oil better than another?
High moly still a thing or not relevant anymore?
- Thread starter BDK
- Start date
4wd
$50 site donor 2026
this. more of nothing makes one better than the other.
you can have fantastic formulations with no molly in it (and use titanium or tungsten for FM), or great Molly based FM that is trimer from infinium that would be more effective than high dose old school Molly compounds
Mazda makes it a thing but you can only get it from the dealer and it’s too expensive. Besides, the manual recommends Castrol. So, is it a thing?
There's several oils on the market with high moly content, but I'm not sure of their availability in Australia. As others have said, a high moly content alone doesn't make a quality oil. By and large, moly-based additives tend to be best performers when acting complimentarily / synergistically with other additives. (like ZDDP) In some formulas, dumping a high amount of moly in the formula can actually make the overall formula worse if there's additive clash. This is why you can't expect miracles from adding a moly-based oil supplement. At best, it does nothing.
Then many use Rotella with great results, very little moly ??
not a great example
CleanSump
Site Donor 2026
Approvals and performance are king. How it's achieved is interesting minutia.