The ornamental design for a truckcab, substantially as shown and described.
FIG. 1 is a perspective view of the truck cab, showing the front, top and
one side thereof;
FIG. 2 is a partial rear elevational view thereof, it being understood that
the lower rear edges of the cab side wall and the inside of the lower
front wall of said cab have been omitted for convenience of illustration;
FIG. 3 is a side elevational view thereof, the opposite side being a mirror
image of that shown; and