Abstract: A trailer tipper is disclosed for dumping material from the rear of a trailer which includes a main frame, a tipping deck mounted at one end of the main frame for supporting the trailer during pivotal movement of the tipping deck from a lowered position to a raised position for dumping the material from the back end of the trailer, a spill chute for receiving material discharged onto the tipping deck during pivotal movement thereof and a shape-modifiable transition chute connected to the tipping deck and the spill chute modifiable by pivotal movement of the tipping deck from a first configuration when the tipping deck is in the lowered position to a second configuration when the tipping deck is pivoted to the raised position.