Yes, I agree that is seeming odd to specify Spring through Fall;
additionally, to omit Summer and “warm weather” driving where a 50wt. is most
necessary. Perhaps the assumed we would know a 20-50wt. is good for
Summer/high heat driving.
Roger, both the VR1
Conventional and Synthetic 20W-50 Racing Oils are perfectly acceptable for
classic car with flat tappet cams to use from spring through fall
months.
If
you have any additional questions please feel free to reply to this email.
Thank
you once again for contacting Valvoline. Dave Valvoline
Product Support