so being winter time i have been going out to truck to start it on cold mornings to let it run a bit before taking off, and while i am just laying/leaning over the driver seat to reach ignition i hold for a bit for glow plugs to do their thing then turn key and engine turns over a couple times then fires right up, this is when i feel my truck kinda move forward then roll back, feels like just and inch or so, i have not felt it if i am sitting in the seat like you are supposed to be sitting, only leaning over the seat reach to start method.
is this a sign of somthing going bad ??

 

My trucks do the same thing. Have since I bought them. I'm not worried about it.

 

Almost any automatic will do that when it's cold out. The fluid in the clutches is thick enough when it's cold to drag on the clutch plates and move the truck against the park pawl.

 

i did not know that, how cold are you experiencing?

 

well 22 deg F today,

the days i noticed it most were in the single digits, and into the minus.

Cold thick fluid dragging on clutch plates sounds good to me, at least its a recognized condition

thanks again

 

my trucks do it too. always wondered why.

 

Mark covered it.

No other explanation required.