Automatic Transmission Delay on takeoff

What is your question?

After engine and Transmission is warm, when Stopped at a Red Light, Transmission has a Very Slight Delay,, and then jerk's on Takeoff. Seem's like the Transmission disengage's while stopped, and then take's moment to engage again. Everything seem's to function good. Good MPG, Engine Smooth. Transmission shift's smooth,, except when cold,, going from 3 to 4th gear. Try's to shift,, but goe's back to lower gear,, after Truck gain's speed,, shift's into 4th,, and finally into 5th. Never had an AT have a delay like this truck does when at a Stop Light, and start going again. Normal or Not?