89 XJ (auto) trouble shifting out of park.

ok so my 89 XJ automatic has 223k miles on it and everything is fine but early in the morning or afternoon, actully any time; the rig has a problem geting out of park. dont get me wrond it gets out of park it just takes a second. it only happens when i havnt driven it that day. i think it might be the fluid levels/ old fluid. please help!

my '89 did this and then i changed the transmission filter and fluid and no problems. cheap and easy project to do.