GM Crossovers to Get Improved Mileage, More Power

At the Chicago Auto Show today, GM officials said to expect the automaker's three-row crossovers to receive similar engineering improvements as the just-introduced Chevrolet Traverse. That means slight gains in power and gas mileage for the Saturn Outlook, Buick Enclave and GMC Acadia.

The improvements come thanks to GM's direct-injection V-6, a potent engine we've driven in the new Cadillac CTS. In the Traverse, the engine makes an estimated 286 hp, slightly more than in the other crossovers. Vehicle line executive Anna Kretz said she expects it to migrate to the Outlook, Enclave and Acadia, though she didn't specify a timetable. We imagine it will happen for the 2009 or 2010 model year.

Gas mileage should also improve, though GM has yet to release exact figures.

"Any time you do a direction injection [engine], you're going to improve your efficiency," Kretz said, adding that she expects the mileage gain to be "certainly one that is noticeable."

With front-wheel drive, the Outlook, Enclave and Acadia get 16/24 mpg city/highway. In the CTS, gas mileage is slightly lower for the direct-injection V-6 versus its port-injected equivalent, but that engine makes 304 hp. If the Traverse's variant can raise highway mileage to 25 or 26 mpg while providing a bump in passing power, it should be a win-win for all.

Comments

GM still has axle ratios that are too tall. They should be 3.16 for front drive, and 3.39 for 'awd'

This new application of the direct injected 3.6 V6 doesn't have the same bottom end power as the naturally aspirated 3.6. The variable resonance intake manifold is omitted from the DI version, at least in the CTS & STS.

Peak torque direct injection, 255ft-lbs@5500 rpm, current 3.6 HO 251ft-lbs@3200.

So if you could see 0.5mpg improvment overall, that would be impressive, seeing as curb weight are 4,750lbs+ for front drive, and almost 5,000lbs for a top of the line Buick.

The thing is, even before the addition of DI, the previous 2008 model lambdas were already getting a class leading 16/24 MPG under the new EPA estimates. That even bests most 5 passenger SUV/CUVs on the market! Some are predicting the DI variant will not only have lower emissions but also increase fuel estimates by at least 1 mpg.

how can you not be impressed with 17/25 MPG from a nearly 5000 lb vehicle? Lots of Traverse info, pics and news at http://www.traverseforum.com