The ornamental design for a vehiclemuffler, as shown and described.
FIG. 1 is a perspective view of a vehicle muffler showing my new design;
FIG. 2 is a plan view thereof; and,
FIG. 3 is a perspective view thereof shown on the rear end of a vehicle.
The broken line showings of the boundaries in the figures and of the remainder of the vehicle rear end in FIG. 3 are for illustrative purposes only and form no part of the claimed design.