I have 97 with the 5.4 in it. When I shift from park to reverse it will stall sometimes, if it doesnt stall it will take a few seconds to engage and shudder. Can anyone help me? Thanks.

 

Could be a number of things....since reverse is a fixed gear, I doubt it to be a tranny issue. I see it as a possible failing of a couple of things. Those being, a possible vacuum leak, especially to the IAC valve. Maybe and only guessing a possible TR (transmission range) sensor needing adjustment or replacement. This may sound odd, but an O2 may be on its way out, since it is shuddering its not adjusting the idle to compensate for the gear load engagement.
This is tough without experiencing it, but maybe this will give you some direction or someone else may be able to assist further.