The performance-oriented Regal GS has a new automatic transmission this year, and is available at dealerships now. The 270 horses of the Regal GS’ turbocharged 2.0L Ecotec engine can now be controlled through a six-speed automatic with Driver Shift Control, and Buick says it will be a no-cost option instead of the existing six-speed manual.

“With the Regal GS, we made a conscious decision to go against the current trend and give enthusiasts the manual transmission they desire as standard equipment” said Tony DiSalle, U.S. vice president of Buick Marketing. “Adding an automatic simply makes the performance of the GS even more accessible.”

The new Aisin AF40 automatic is calibrated specifically for Buick’s most athletic sedan. With the car’s Interactive Drive Control System set to “GS” mode, the transmission delivers firmer shifts, aiding performance. Acceleration matches the manual with an estimated 0-60 mph time of 6.7 seconds.

EPA-estimated fuel economy of 19 mpg city and 27 on the highway, standard performance components like Buick’s innovative HiPer Strut front suspension and Brembo front brake calipers, and optional features are identical regardless of the transmission.

Starting with 2013 models, eAssist will be standard on the Regal with the discontinuation of the 2.4L base model. eAssist uses a compact lithium-ion battery pack and a small electric motor to "assist" the gas engine. The system provides an electrical boost to the engine at low speeds and on inclines where fuel efficiency can suffer most. Estimates pin the Regal eAssist at 36 MPG for the highway.

“Buick is committed to increasing innovation across the lineup,” said DiSalle “By making the advanced eAssist powertrain standard on a second vehicle, we are putting the spotlight on smart technology.” Buick also began offering eAssist on the 2012 LaCrosse as the standard powertrain.

Pricing and an on-sale date for the 2013 Regal with eAssist will be announced later this year.

theCD's take: We're glad to see Buick offer such a variety of powertrains for one vehicle, from the eco-conscious driver with eAssist to the performance-minded with GS. If you're in between, look at the Regal Turbo.