The ornamental design for a trackunit for snowvehicle, as shown and described.
FIG. 1 is a perspective view of a track unit for snow vehicle showing my new design in its environment;
FIG. 2 is another perspective view thereof, enlarged;
FIG. 3 is a right side elevation view thereof;
FIG. 4 is a left side elevation view thereof;
FIG. 5 is a top plan view thereof;
FIG. 6 is a bottom plan view thereof;
FIG. 7 is a front elevation view thereof; and,
FIG. 8 is a rear elevation view thereof.
The dashed line showing of structural lines is included for the purpose of illustrating non-claimed subject matter and forms no part of the claimed design.