Automatic transmission warm up in Park or Neutral?
No difference , just start vehicle wait a few seconds then drive off.
Seconds? The fluid? Nothing warms in the transmission if it sits and idles at -20?
I once took off cold, in the winter, hammered on it and blew tranny fluid on the ground. I don’t remember if it was a line or seal. I do remember my ‘friend’ from school charged me $1000 to fix it
Drive gently until it warms up.
Auto transmissions are crabby about oil that is too hot but within reason, are very happy with cold oil. Big diesels are idled for quite a while to let air pressure build. You can take off reasonably once engine oil pressure shows. Don’t worry about the trans. Auto trans that self-destruct in either cold or hot weather usually have had no maintenance since they were built.
Karl
Agree. The diesels run much better and cleaner with a little more idle time then gasoline engines. The colder it is, the longer it takes. I would baby a truck more with its separate diffs then fwd cars. The trans axle, transmission and engine are all in one unit and warmup quickly in fwd cars. A truck, IMO, should be driven a little slower, a little longer at low speeds.
Thanks JT. 