[5] In 1924, Purolator filters were made available for retail sale for both passenger cars and trucks[6] and Motor Improvements president James A. Abeles announced it had established a network of 2,600 sales, installation, and service stations across the US and Canada[6] and had engaged ad firm MacManus, Inc. for a nationwide advertising campaign.

[9][10] Among its acquisitions in 1965 was Stant Inc., a Pine Bluff, Arkansas manufacturer of radiator and fuel caps which continued as an independent subsidiary of Purolator.

[25] By the end of 1983, Purolator operated 270 terminals, 111 aircraft, and 5,328 ground vehicles and reported it had handled 76,841 packages in the year.

While revenue rose in the third quarter of 1984, earnings declined due to the company's heavy investment in new equipment as it continued expansion of its courier business.

The company had spent significant capital building an air fleet in previous years, an endeavor that analysts partially blamed for its financial decline.

[34] In 1988, Facet and its subsidiaries including Purolator were acquired by Pennzoil for US$254 million[35] after having been the target of hostile bidder, Prospect Group.

The resulting subsidiary was expected to be the world's largest automotive filter company and hold a 30% share of the US market.

[28] In February 1990, Pennzoil put Facet up for sale having been unable to realize expected synergies from the filter manufacturer.

[35] In 1994, Purolator was acquired by engineering company Mark IV Industries of Amherst, New York for a reported US$273 million.

[45] By 1970, it was sponsoring NASCAR Cup Series team Holman-Moody with driver David Pearson, winner of multiple Grand National Championships.