LAS VEGAS – More and more car shoppers use social-media websites to obtain vehicle information and peer advice, says a new survey on modern buying habits.

And after a purchase, many consumers log on to those sites to comment on their new vehicles and buying experiences, according to the joint study by Dealer.com, DrivingSales and GfK Automotive Research.

That online activity presents opportunities for alert auto makers and dealers to identify “loyalists” and ask them to share their automotive views with others online, says Kevin Root, Dealer.com’s chief product officer, here at the DrivingSales Executive Summit presented with WardsAuto.

“If a dealership asks for reviews, most people are willing to post them,” Root says. “Foster that relationship.”

He recommends dealers step up post-purchase marketing efforts in that way. Typically, a dealer spends a lot of money and effort trying to get the sale, but little on cultivating the customer post-purchase.

About 40% of 2,000 people polled identify themselves as staunchly loyal a brand or dealership, “unless the relationship is screwed up,” Root says.

But the study indicates only 25% of the time does a dealership or auto maker ask someone to “like” them on Facebook. “It’s a big miss,” he says. “Of the ones that were asked to do that, 82% did it.”

Facebook is the Internet’s dominant social-media site. Others include Twitter, Google+ and YouTube.

The exponential power of social media is awesome, Root says, noting the average Facebook user has 170 friends, and each of those has about the same number.

“It used to be that if you got a customer mad at you, they might tell six or seven friends,” he says. “With social media, they tell a lot more.”

One of four buyers use social media to post comments about a newly purchased vehicle, while 44% post comments about vehicles in general, the study says.

Eighty-two percent of the comments are positive, which may allay dealers’ fears of social-media smear campaigns, Root says.

“Positive customers use social media as an avenue, while negative customers are mad and looking for an avenue,” says Matt Murray, Dealer.com’s director-digital marketing.

Sixty-five percent of the survey participants say reading other people’s favorable social-media posts influenced their car-buying decision.

More than 40% say reading such positive comments prompted them to add a particular vehicle to their shopping list, while 28% added a dealership.

sfinlay@wardsauto.com