LOUISVILLE, Ky - What in the name of Colonel Harland Sanders is going on at KFC?

The chain built by his secret recipe for fried chicken is about to give equal billing to, gulp, grilled chicken.

Kentucky Fried Chicken customers will be greeted eventually by lighted "Now Grilling'' signs, starting in coming weeks in select U.S. cities.

Storefront signs will be altered to promote the new product -- called Kentucky Grilled Chicken.

Even the brand's ubiquitous chicken buckets will get a makeover.

Doug Hasselo, KFC's chief food innovation officer, says: "This is transformational for our brand.''

Louisville-based KFC, a subsidiary of Yum Brands Inc., hopes grilled chicken will lure back health-conscious consumers who dropped fried chicken from their diets, or cut back on indulging.

KFC announced last year that fried chicken at all its U.S. restaurants had zero grams of trans fat per serving after the chain switched cooking oils.

KFC says the grilled chicken has significantly fewer calories and fat, plus much less sodium, than its Original Recipe fried chicken.

The chain says it now serves some 12 million customers daily at more than 14,000 outlets around the world.

The grilled product, served on the bone, is being tested in six cities -- Indianapolis, Colorado Springs, San Diego, Oklahoma City, Jacksonville, Fla., and Austin, Texas. A national rollout is planned early next year.

The company says prices for grilled and fried chicken will be comparable.

KFC executives insist the chain is not backing away from its most famous product. New fried chicken items are planned this summer.

Larry Miller, a restaurant analyst with RBC Capital Markets, said the chain faces a possible "speed bump'' in winning over health-savvy consumers. But if grilled chicken becomes a hit, it could boost KFC's U.S. performance, which has lagged behind its burgeoning China business, Miller said.

"If they can get people over the hump -- which is `Do I believe KFC can sell me a healthy alternative' -- they'll increase their (customer) frequency,'' Miller said. "I don't see too much risk in trying it.''

KFC executives say the company has a new oven that grills a batch of chicken in just over 20 minutes.

Jayne Hurley, senior nutritionist with the Center for Science in the Public Interest, a Washington-based advocate for nutrition and health, said KFC deserves credit but the chain lagged behind competitors.

The grilled chicken easily beats KFC Original Recipe fried chicken in calories, fat and sodium, but Hurley warned a grilled chicken breast contains 600 milligrams of sodium, slightly more than a third of what someone 50 years or older should consume daily. By contrast, an Original Recipe fried chicken breast has 1,020 milligrams.

KFC plans to change "Kentucky Fried Chicken'' storefront signs to add grilled to the name. Chicken buckets will still feature KFC founder Sanders but will get a redesign.