This is from The Imperial Oil Marketing Plan to Introduce Imperial Marvelube Oil, a 14 x 17 1/2 publication to introduce the new product to the dealers. It was Feb 1926, there were 6 grades of oil. Marvelube was available till well after the Esso rebranding which occurred in 1948 ( not positive on that Date)
This from the dealer newsletter "The Salesmotor"on April 20th Marvelube went on sale across Canada. June 1st to meet this unfortunate demand-we have doubled our plant capacity. Also dealers were repeatedly selling out. Exclusive use of Peruvian crude.is the reason for its success in september of 1926 Gasoline with Ethyl was introduced.
Hope that helps..dodogas