If I am waiting at a long light is it a good or bad idea to pop the car in neutral as to not wear out trans parts? I always thought this was a good practice but not sure now. when my car is cold it is reving high and seems to put a lot of load on the torque converter.

I usually just put mine all the way in park.

If its known that I'll be there for more than 2 min then I'll take it out of gear.
Usually I leave it though.

when i pull up to a train, i put it in park and turn the car off. why waste gas if i dont have to?

my driving style takes care of that already

I'll sometimes stick it in N if I know I'll be there a few minutes and I want to give my left foot a rest. Otherwise, in OD/D it stays.

Also, my engine mounts are wonky, so another reason I refrain from doing it.

For those of you with scangauges you can monitor trans temp and see if it makes a difference or not. Personally my trans temps have not ben going above 130 when its less than 30 F outside, no matter engaged, idle, or neutral.

doesnt starting the car use quite a bit of gas as well? im not sure how it would compare to it running, i guess it would depend on how big the train was. But i know alot of starting and stopping is a good gas mileage killer.

Startup is also the worst thing you can do to your engine, although if you only have it off for a few minutes then things are probably still pretty well lubricated.

I have been know to turn mine off and put er in park... Or I just hold my brake. I should be putting in Netural tho. Good idea.

if i am sitting for a while i just throw the parking brake on and let her sit in the drive gear

in i have to get out of my car for a short period and im leaving the car running i leave the car in gear and then just set the parking brake....i do that alot....less wear on the trans