Has anyone else experienced a noise that sounds a bit like a pig snorting when accelerating? It is very brief when you first pull off from a stop or slow roll. Probably nothing but you never know if it's a sign of something else that may need sorting.

 

The only thing that pops to mind, might be a resonant flutter of the throttle plate - ESPECIALLY in you have modified the air intake in any way. I had a Town Car one time that had a factory recall for a 'moan' sound coming off idle or red light stop. The Recall fix was addition of an air 'expansion' chamber behind the manifold. That is the purpose of the large baffled chamber on this generation trucks air intake. Have you modified or drilled holes in the intake?