At the NY aauto show...

The V-Series version of Caddy's hardtop roadster gets not only the new supercharged Northstar engine, and a 0-60 mph time of less than 5.0 seconds, it also gets the first rear-drive application of GM's new six-speed automatic transmission.

Come on GM lets get it for the C6 also.

|UPDATED|3/23/2005 1:00:01 PM (AZT)|/UPDATED|

GM's option list for the 2006 model has option

mx0 transmission, 6 speed auto.

I think GM plans to put the transmission in in the coupe and convertible but it is not an option in the Z06

Unfortunately, the Montana dealer that posted the bit about C6 and 6 speed auto in 2006 has taken it back. The Caddy (XLR not SLT) announcement at least gets it near the Corvette in the Bowling Green plant.

Here is some text from Autoweek. The 6 speed and the car are supposed to appear in the first Quarter of 2006.

Power routes to the rear wheels through a new rear-mounted, six-speed automatic transmission that incorporates some of GM’s best features, such as Performance Algorithm Shifting, which prevents upshifts in high-lateral acceleration maneuvers even if the driver lifts off the accelerator, and Performance Algorithm Liftfoot, which minimizes upshifts during closed-throttle driving and cornering to prevent unnecessary shifting.

Doesn't having a six-gear auto also help save gas at highway speeds?

To answer Adam's question and look at the "why" of a 6 speed auto lets work some numbers:

The various first gear thru top gear ratios are:

4L65E (A4)= {3.06,1.63,1.00,0.70} (4 speed auto)
6L80E (A6)= {4.027,2.364,1.532,1.152,0.852,0.667}(6 speed auto)
T56 (M6) = {2.66,1.78,1.30,1.00,0.74,0.50} (6 speed manual)

Some quick calculations give the following torque multiplication factors for axle ratios times tranny gear ratios. These use the Corvette axle ratios with the known Caddy A6.

2.56*x6L80E = <10.31, 6.05, 3.92, 2.95, 2.18, 1.71> (*expected axle with A6)
2.73*x4L65E = < 8.35, 4.45, 2.73, 1.91> (*current std A4 axle)
3.15*x4L65E = < 9.64, 5.13, 3.15, 2.21> (*current hi perf A4 axle)
3.42*xT56 = < 9.10, 6.09, 4.45, 3.42, 2.53, 1.71> (*current M6 axle)

Comment 1: The last number in each series is the top effective axle ratio. The 1.71 ratio of the 6 speed manual is matched by the 6 speed auto! Yes Adam that should give a better highway EPA rating.

Comment 2: The 10.31 first gear of the A6 might require a very large tire budget.

Comment 3: The A6 appears to give the best of both worlds. These data were first assembled by RK on another board.

|UPDATED|4/8/2005 9:22:27 AM (AZT)|/UPDATED|