3 out of 4 vehicles I have/look after, take 5 quarts synthetic for an oil change. I usually have a supply of oil ready for each vehicle, either through an Advance Auto Synthetic Sale, or a 5 quart Walmart jug. Using different synthetics in each (Synpower, Q Horsepower, Mobil 1).
Since Napa is made by Valvoline, I'll assume it's ok to top off the Valvoline with Napa Synthetic (if necessary). But what about the other brands? I was thinking of getting a few quarts as back ups, just in case. I'd rather spend $3.29 a quart, than $6+ to use as top off oil. Or should I stick to the same brands for each?
Off Topic: Got my $10 Valvoline Synpower Rebate in the mail yesterday! In under 4 weeks!