Anyone know why? There are no mechanical changes.

 

raised standards maybe?

 

That's my guess.

 

Thats pretty weak...

 

Is it getting an automatic?

 

I thought I heard that pretty soon all manufacturer's have to meet 25 mile per gallon standards soon. I don't know maybe I was dreaming heh.

 

Elimination of the 1-4 skip shift feature would do it. Who knows for sure.

 

The '05 model had it too. The way I understand it is that when the LS6 engine was shared with the Z06, they were able to average the mileage results between it and the CTS-V. But the mileage results dropped for '05 when the CTS-V had the LS6 to itself. That didn't make any sense to me, but the numbers dropped from 16/26 in '04 to 15/22 in '05, running supposedly the same engine.

Is it possible that there were calibration changes to meet the LEV-2 emission standard (as opposed to the old LEV-1 standard) that cost a few 10ths of a gallon on the '07 model. At 16/25, they were just barely above the 22.5 combined rule.

 

I thought the CTSv switched to LS2 power for '05?

My wild assed guess is they're putting an automatic in it to boost sales and it can't beat the tax with the 4L60E...just like the GTO.

 

Chris, the '05 still used the LS6, believe it or not...

 

There is a new (more realistic) system for measuring fuel economy. I don't think the EPA is requiring adoption of the new system yet, but it appears that GM is using it already.

 

That's not it either. I've never seen very good explanations for a lot of these things. I'm sure they're out there -- just not explained.

For example, does anyone remember that the automatic LS1 Camaro lost 1mpg between 2001 and 2002? It was rated 18 city in 2001 and 17 city in 2002. These EPA mileage ratings can be affected by the mix of equipment in the fleet. If some percentage of the cars have a sunroof, then you have to test with a sunroof, and that can put you into the next weight category. A few years ago, the Lincoln LS V8 with the sport package couldn't be had with the big subwoofers in the premium sound system, because the bigger wheels in the sport package weighed more, and combined with the heavy subwoofers, would put the car into the next weight category where it presumably would have had a guzzler tax.

Remember that whether you got the 2.73 or 3.23 axle, the Camaro had identical EPA ratings? Except that if you were to run a 2.73 car over the EPA cycle, it certainly would have done better than a 3.23 car.

There's a lot of number jockeying and game playing with these EPA numbers. Take them with a grain of salt. My guess is that a minor calibration change for emission regs or a change in equipment mix probably made the difference, assuming that the info about no mechanical changes is correct (an automatic would be a significant mechanical change, btw).

Too bad that the CTS-V price will go up by the guzzler tax, if this does indeed come to pass.

 

Nah, there would be no reason for them to test it with the new way if they knew it was gonna be hit with a gas guzzler tax.