To D or not to D

I know this is a stupid question and I'll probably catch a few smart remarks but here it is, while driving around town (rarely over 40 or 50), should I be in 4th gear or D (overdrive) gear?
While in D around town, the tach is around 1000 or less, seems kinda low to me,
Thx

 

If I'm in heavy traffic, I'll slip down to 4th to keep the truck from going in and out of overdrive. Normal city driving though without traffic I just use Drive.

 

If you are cruising, and don’t need the extra on demand power, keep it in D. If you are in heavy traffic and need on demand power and quicker shifiting, keep it in 4th.

 

great, thanks for the info guys,

 

I throw it in 4 all the time to make trafficy conditions way more pleasant. Way easier to coast in a lot of situations that way.

If it get real bored I’ll pretend I’m a manual and shift up thru the gears all the way to D lol.