On 5 Mar 2010 22:22:59 GMT, ddl@danlan.*com (Dan Lanciani) wrote:

In article , (Doug Miller) writes:
| In article , ddl@danlan.*com (Dan Lanciani) wrote:
|
|
| I'm sorry if this is a stupid question, but I really don't know:
| typically, does shifting an automatic transmission into neutral
| actually disengage a gear or does it merely cause the torque
| converter to stop transferring torque?
|
| Neither, actually. It disengages a clutch inside the transmission.

Interesting. Is disengaging that clutch used for anything else (except
perhaps park)? If that clutch on my vehicle were not fully disengaging
would I likely observe any other symptoms or would the torque converter
absorb the rotation in park and at idle in neutral with the transmission
loaded (i.e., with the transfer case not in neutral)?

Dan Lanciani
ddl@danlan.*com

There is more than one "clutch" involved - and in most transmisions
also at leat one "band" or "brake". They are applied in different
combinations for different gears.
Your tranny uses planetary gear sets, and by holding different
elements of the set, different ratios are produced. Locking the input
to the output with a clutch gives direct drive.

If any of the clutches do not release fully the fluid will quickly
overheat and stink.
Even fully released, with no load on the output shaft it will turn
when the engine is running in neutral because of viscous friction (oil
between the plates of the clutches etc)