General Motors Co. said this week the 2015 Chevrolet Corvette gets a 3.5 percent boost in fuel economy when paired with the company’s new eight-speed transmission, which is being built in Toledo.
That works out to a gain of one mile per gallon on the highway, allowing the sports car to achieve 29 miles per gallon to go along with its 460 horsepower. The car’s city and combined cycle ratings were unchanged.
For such a complex transmission, that seems like an awfully meager return, but industry experts say the transmission has far more potential for delivering efficiency than it shows in the Corvette.
And let’s be honest. People don’t buy Corvettes for their fuel economy. They buy them because they look good and go fast.
No disappointments there.
GM said the eight-speed Stingray does 0-60 in 3.7 seconds, a tenth of a second quicker than it did with the old six-speed. It’s also a tenth of a second quicker in the quarter-mile.
GM has been working on the eight-speed project for several years. The company invested a total of $260 million in the Toledo Powertrain Plant on Alexis Road to prepare it to build the gearbox, which officials have touted as the company’s most advanced transmission ever.
Dan Edmunds, director of vehicle testing at Edmunds.com, said the Corvette isn’t the vehicle where the eight-speed will shine — at least not in terms of fuel economy.
“The trick is to develop the architecture where you have a transmission that can shift through eight gear ratios, and you can adjust what those ratios are and when the car shifts based on what kind of car it’s in,” he said.
In the case of the Corvette, it’s likely GM engineers could have squeezed out more fuel economy, but that might have hurt it in terms of speed. Plus, the Corvette already gets good mileage for a high-performance car, and Mr. Edmunds said having eight gear ratios instead of six should also make the car much more driveable around town.
Currently, only the Corvette and some heavy-duty pickups are confirmed recipients of the new transmission. But as GM continues to chase better fuel economy, it figures to use the eight-speed in a range of vehicles. Mr. Edmunds and others suspect all GM trucks will soon get it.
Ray Wood is president of United Auto Workers Local 14, the unit that represents workers at the Toledo Powertrain Plant. He said eight-speed production is light right now, but it will ramp up quickly, with plans calling for 500 a day by the end of September.
“It might push us a little more than we want to be pushed, but we’ll put out a quality product. Everything’s still on course,” he said.
GM has brought more workers into the Toledo plant in recent weeks, though to this point they’ve all been current employees who are laid off from other GM facilities. That includes Defiance, where GM has a casting plant.
In a statement, the company said it had “recently informed employees that it will consolidate some areas of plant operations for potential future growth. As a result, personnel moves occurred, and some employees accepted transfers to surrounding GM facilities.”
A company spokesman did not respond to an inquiry asking how many people were affected by the moves.
GM said Defiance Casting currently employs 1,200 hourly and salaried employees.