Is GF-4 rating equal to GM4718 for Syn?

[Ruby Fan]

I have found a Valvoline Syn that shows a GF-4 rating, but does not show the GM-4718 rating. Is the GF-4 rating equal to or an upgraded rating for use in Corvettes? I don't know what the late model Vettes require, and I was wondering if the GM-4718 rating is being superceded or dropped as our C-4's are getting older. Maybe going to a newer rating. Some Syn oils still carry GM-4718 rating, but I noticed that a Mobil-1 didn't have it, unless I looked at the wrong weight. Thanks

 

[Hib Halverson]

GF-4 and GM-4718 are not the same, but they do test some, but not all, the same qualities in an oil, however, GF-4 applies to both petro-based and synthetic oils. Generally, the only oils which can meet GM4718 are synthetics.

If 4718 ever is superceeded, it will be replaced by a more stringent spec. so, anything that meets such a new spec, will also meet the old one.

A good choice is Mobil 1 10W30.
An even better choice is Red Line 10W30.