Depends on what you are replacing.
If you are replacing JUST THE BULB, no problem in most cases.. However SOME LED lamps are kind of fussy as to HOT and Common (Ground) leads.. Some tail lights on trailers MIGHT be "odd" but I would expect this to be very very very rare.
(Dual element lamps like the 1157 MUST have the "Shell" grounded or they do not work properly)
Page 2: If you are replacing the ENTIRE lamp assembly.
ONly problem is making sure the new one is as large as or larger than the old one. so it does not show that you swapped them.