The Collaborative International Dictionary of English v.0.48:

Truckler \Truc"kler\, n.
   One who truckles, or yields servilely to the will of another.
   [1913 Webster]

WordNet (r) 3.0 (2006):

truckler
    n 1: someone who humbles himself as a sign of respect; who
         behaves as if he had no self-respect [syn: apple
         polisher, bootlicker, fawner, groveller, groveler,
         truckler]

Moby Thesaurus II by Grady Ward, 1.0:

44 Moby Thesaurus words for "truckler":
   apple-polisher, ass-licker, backscratcher, backslapper, bootlick,
   bootlicker, brown-nose, brownie, clawback, courtier, creature,
   cringer, dupe, fawner, flatterer, flunky, footlicker, groveler,
   handshaker, helot, instrument, jackal, kowtower, lackey,
   led captain, lickspit, lickspittle, mealymouth, minion, peon,
   puppet, serf, slave, spaniel, stooge, suck, sycophant, timeserver,
   toad, toadeater, toady, tool, tufthunter, yes-man