Automatics are more efficient?

[Ryland]

Many manual transmission's are sold in the model only, so you get wider tires, sun roof.
It's not always a fair comparison.

[Qsport? UOTE=Xist;503110]I have read that auto makers can tell the EPA how to shift. Someone suggested that they want to make the automatic transmissions look more efficient, so that people have another excuse to spend more money.[/QUOTE]

[IamIan]

A bit dated 1999 .. but .. PDF Link

[secaturbo]

Other problem with the newer Manuals is they have to lower the final drive ratio (spin the motor higher) so the car can cope with hills in cruse control mode.
Found that out the hard way on a Nissan Axxess van. At 65 the auto turned about 500-700rpm less then the manual. Maybe more can't recall.

Heres example of Camaro
SS 6-speed automatic final drive = 3.27
SS 6-speed manual final drive = 3.45

[Miller88]

Some vehicles have a larger spread than that, even. The Renegade has 3.27 for the 9 speed auto, but the 6 speed manual is 4.44

[gone-ot]

Most automatics have a torque-converter which effectively multiplies engine torque whenever the converter is NOT operating in lock-up.