Originally Posted by StarCaller
Quote
fact, chains last longest with 30 viscosity oil
why would that be?
the higher the viscosity, the higher the longevity ?
how about using a 0w-40?
better or worse than a 30 ?
For reducing the wear in the timing chain, HTHS has no role, which governs the hydrodynamic lubrication. It is boundary lubrication in the valvetrain and timing chain, and that is related to the base-oil viscosity instead. Some 0W-20 and 5W-20 oils will do better than 5W-30 and even 0W-40 because they have a higher base-oil viscosity. See my spreadsheet.
Estimated base-oil viscosity (BO DV150) and VII content of selected oils
Quote
fact, chains last longest with 30 viscosity oil
why would that be?
the higher the viscosity, the higher the longevity ?
how about using a 0w-40?
better or worse than a 30 ?
For reducing the wear in the timing chain, HTHS has no role, which governs the hydrodynamic lubrication. It is boundary lubrication in the valvetrain and timing chain, and that is related to the base-oil viscosity instead. Some 0W-20 and 5W-20 oils will do better than 5W-30 and even 0W-40 because they have a higher base-oil viscosity. See my spreadsheet.
Estimated base-oil viscosity (BO DV150) and VII content of selected oils