The Collaborative International Dictionary of English v.0.48:

chuck-full \chuck-full\ adj.
   same as chock-full. [predicate]

   Syn: chockablock(predicate), chock-full(predicate),
        chockfull(predicate), chockful(predicate),
        choke-full(predicate), cram full.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

chuck-full
    adj 1: packed full to capacity; "chowder chockablock with pieces
           of fish" [syn: chockablock(p), chock-full,
           chockful, choke-full, chuck-full, cram full]