AZjeff
$50 Site Donor 2023
High Mileage versions of engine oils have extra seal restorative products in them that can actually restore a seal and stop it from leaking if it has just dried out from too much use of a synthetic engine oil. Some synthetic engine oils will dry out the RMS and start it leaking.
This quote came from a respected long time member on another automotive forum I frequent. No use trying to clarify since it would result in an ugly dog pile for insinuating the esteemed member wrong. Some myths just won't die.