The Garbage Truck/Trash Cart Robot is a minor character in WALL•E. He is a hovering cart like robot that carries Axiom trash and dumps it into a trash chutes that lead to the Axiom Garbage Disposal where WALL•A units will handle it.
The Garbage Truck Robot looks like a bit similar to MVR•A, but when he is mostly white, the Garbage Truck Robot is gray in color, and he has black and yellow warning stripes (MVR•A has black stripes too, but not the yellow ones).
Two Garbage Truck Robots appear in the movie, but only briefly. It is clear that these robots are two separate units, because their coloring is different. The first Garbage Truck robot is seen by WALL•E, when he tries to reach MVR•A carrying EVE. This Garbage Truck Robot dumps trash into a trash chute near WALL•E. The second Garbage Truck Robot is seen by EVE, when he dumps trash to a trash chute that is connected to the Captain's Quarters. When that Garbage Truck Robot leaves, EVE flies through the same chute and brings the plant to the Captain.