Re: [A/S] transmission temps = transmission life

["Carol and Oliver Filippi" <ofilippi@xxxxxxxxxxxxx>]

I have a 2002 Chevy Silverado 3/4 ton with the 6000 gas engine and overdrive
automatic (not the Allison).  The instrument package includes a transmission
temperature gage.

The owner's manual says the following about transmission temperature:
"The normal operating range is from 100 degrees F (38 C) to about 265
degrees F (130 C).

At approximately 265 degrees F (130 C) the message center will display a
Trans Fluid Hot message and the transmission will enter a transmission
protection mode.  When the transmission enters the protection mode, you may
notice a change in the transmission shifting patterns.  The transmission
will return to normal shifting patterns when the transmission fluid
temperature falls below 260 degrees F (127 C).

If the transmission fluid reaches temperatures of approximately 275 degrees
F (135 C) or greater, the message center will display a "Trans Hot ..Idle
Eng" warning message.  Pull the vehicle off the roadway when it is safe to
do so.  Set the parking brake, place the transmission in Park (P) and allow
the engine to idle until the transmission temperature falls below 260
degrees F (127 C).  If the transmission continues to operate above 265
degrees F (130 C), please contact your nearest dealer or the GM Roadside
Assistance Center."

This transmission uses the new Dexron III automatic transmission fluid
(ATF). [which may have a slightly different temperature operating range (or
heat resistance) than the older Dexron II - probably not much different]

I think this is a pretty good guideline for transmission operating
temperture range. Since it is in the owner's manual, it is probably
conservative.

The current crop of computer managed engines and transmissions tend to be
smarter than the driver.  They are designed to prevent (as much as possible)
the driver from damaging the vehicle.

Oliver Filippi