Automotive manufacturer loyalty levels—or how many vehicle customers repeatedly buy the same brands—dropped from 49.1% in 1998 to 39.9% in 2008, according to data from an Experian study that showed various ironies in the area of customer loyalty.

While the Toyota brand scores highest (59.8%) in consumer loyalty to an automotive nameplate, its kid-brother brand Scion scores lowest (19.8%).

Another irony is that customer satisfaction does not necessarily equal loyalty. The Lincoln and Jaguar brands scored highest in customer satisfaction, yet ranked 11th and 14th respectively among 20 brands in loyalty.

That satisfaction-loyalty disconnect may stem from customer satisfaction scoring often being swayed by dealerships that “coach” buyers to rate them highly on surveys sent to auto makers.

Scott Waldron, president of Experian Automotive, a division of Experian plc., an information-services company.

Another irony is that despite their economic disparity, the most-affluent car buyers ($200,000 and over household income) and the least-affluent ($25,000 and under) showed similar corporate loyalty levels — which on both ends were lower than allegiance demonstrated by consumers in middle income brackets.

Rich people have more auto brand choices open to them, Waldron says, while the least affluent are not particularly loyal because so few vehicle choices are available to them.

The No.1 highest loyalty driver was leasing. Also, auto makers’ captive financing companies help boost consumer loyalty to the manufacturer and dealer alike, says the study. Captive financing gave a 20% loyalty boost to auto companies and a 27% boost to dealers compared with financing from outside sources.