Would car rental companies count? Enterprise rentals (and others) use quickie lubes, and the local quickie lubes that service them around here use mostly Valvoline bulk oil.
Know this graph is a little old, but Valvoline bulk goes into Speedee oil change places, some Jiffy Lubes (most use SOPUS, some do use Valvoline), Grease Monkeys, and over 1700 Valvoline branded quickie lubes. I'd say they are 'Majors" - Valvoline is probably only beaten out due to Jiffy Lube using Shell
So if there are 1700 Valvoline quick lubes pushing 30 cars a day (realistic) and only 1300 Honda and Acura dealerships (we'll give them 40 cars per day, which is doubtful) then they are pretty close to equal right then and there. 51,000 to 52,000
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Here is a newer market share but unfortunately it's sorted alphabetically. Still, Valvoline is in the top 5
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