Why trans hesitates on 2006 Dakota 4x4 4.7

Started last winter, when I put trans in drive it hesitated about 5 seconds before moving forward. It's now doing it in warmer weather. What could be causing this? Thanks

When was the last time you changed the fluid a filter in the trans.

the filters are know to seperate at the plastic/metal conection and suck air causeing weird stuff, seen it a few times myself.

There's a TSB on the problem:

http://dodgeram.info/tsb/2006/21-007-06.htm


NUMBER: 21-007-06

GROUP: Transmission

DATE: April 07, 2006

THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 21-016-05, DATED SEPTEMBER 01, 2005, WHICH SHOULD BE REMOVED FROM YOUR FILES. THIS IS A COMPLETE REVISION AND NO ASTERISKS HAVE BEEN USED TO HIGHLIGHT REVISIONS.

SUBJECT:
RFE Transmission Filters - Delayed Engagement And Related Transmission DTC'S

OVERVIEW:
This bulletin involves verifying the build date of the transmission, and if necessary, the replacement of both the cooler return and sump filters in the transmission.

MODELS:

2005 - 2006 (DR) Ram Truck

2005 - 2006 (HB) Durango

2005 - 2006 (KJ) Liberty / Cherokee

2005 - 2006 (ND) Dakota

2005 - 2006 (WK / WH) Grand Cherokee

2006 (XK) Commander

NOTE:
This bulletin applies to vehicles equipped with the a 45RFE or a 545RFE automatic transmission (sales code DG4 or DGQ respectively) having a specific transmission build date code (see the below DIAGNOSIS section for further details).

SYMPTOM/CONDITION:

The customer may experience an initial delayed shift engagement following an extended off (not running) period of time, generally after being parked overnight. The initial shift engagement may feel like a delay or slip when a transmission gear (reverse or drive) is first selected after engine start.

I get the same thing sometimes in my 2007 Ram. I shift from drive to park and back a couple of times and it works fine afterward.
I change the fluid and filters sooner than the factory schedule. It has done this from about 40,000 miles to the current 312,000 miles.