« Reply #21 on: December 26, 2012, 09:14:09 PM »
one thing that seems to help with the automatic transmissions is to start them in neutral and let it warm up that way.
This is completely true.
In neutral your torqueflite transmissions fully charge the torque converter. In Park the torque converter is allowed to drain down somewhat, so the resistance on the motor is slightly less. With slightly more resistance and slightly higher internal pressures the trans will warm up faster.
The bigger difference is really that if you slam it into drive from Park the torque converter sometimes lags and does not top off instantly, causing a slow start initially. The shifts are very soft and slow until the pressure catches up. This is especially true of worn or aged transmissions. The torque converter fluid level is also the reason (besides manually limiting the up-shift RPMs) you'll sometimes see a difference between starting in "1" versus "D".
Ever notice that you're supposed to, according to the service manuals, have your car in "Drive" stopped by the emergency brake when accurately checking the fluid level? I always check mine with it running in "Park," but that's not totally accurate. If the engine isn't running the fluid level will look much higher than it actually is because the torque converter is allowed to drain down fully. With the engine running the torque converter is filling at the same time its draining, so it stays high enough to check with the dipstick.
« Last Edit: December 26, 2012, 09:21:59 PM by captspillane »
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Currently Inspected and Insured as of Jan 2013:
-1985 Eagle Station Wagon 258 T5 Stickshift
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-1982 Eagle SX4 258 T5
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