[70AARCUDA]

...time to go searching for the "specs" that'll "...tell the tale..."

 

[70AARCUDA]

...would be better if it only required a reprogramming!!!

 

[70AARCUDA]

Improved powertrain efficiency.

...reduced "pass-thru" losses.

 

[70AARCUDA]

...unfortunately, it (milage increase) was accomplished by reducing the axle-ratio from original 3.87:1 down by 9% to 3.53:1.

 

[70AARCUDA]

So all 2012 automatics have the new axle-ratio?

...standard on LTZ and Fleet cars, optional on 1LT, 2LT and Eco models:

Axle, 3.53 final drive ratio 1 - Included and only available with (MH8) 6-speed automatic transmission.

--

S

A[SUP]1[/SUP]

A[SUP]1[/SUP]

S

A[SUP]1[/SUP]

...where (from left to right):

-- = 1LS = Not Available
_S = 1FL = Standard for MH8 fleet cars
A1 = 1LT = Available MH8
A1 = 2LT = Available MH8
_S = LTZ = Standard MH8
A1 = Eco = Available MH8

...RPO-code FXH is the 3.53:1 axle ratio.

...more info here: http://eogld.ecomm.gm.com/NASApp/do...egionID=1&divisionID=3&vehicleID=11503&type=0

 

[70AARCUDA]

EPA "tests" are done on dynamometers, not around a tract. The dynamometers are "loaded" to simulate a total "road" load (tires, aero, mechanical, etc.), but there's NO extraneous electrical loads, ie: NO day-light running lamps, NO road/fog lamps, NO radio/media, etc.