Thanx for that link!
It adds a consistency to the argument that GL4= Appropriate for usage in applications where "yellow metals" (brass, bronze, copper) are involved, and GL5=appropriate for all other applications such as differentials and current production transmissions.
It makes sense and would also explain why someone marketing an oil product for current applications would claim compliant for both standards - if no transmission manufacturer uses yellow metals anymore. Anyone aware of the use of yellow-metal for friction surfaces in modern transmissions?
