The ornamental design for an oiltank with transparentsides, as shown and described.
FIG. 1 is a perspective view of the subject oil tank with transparent sides illustrating my new design;
FIG. 2 is an end view of the oil tank with transparent sides;
FIG. 3 is an opposite end view of the oil tank with transparent sides;
FIG. 4 is a bottom view of the oil tank with transparent sides;
FIG. 5 is a top view of the oil tank with transparent sides;
FIG. 6 is a side view of the oil tank with transparent sides; and,
FIG. 7 is opposite side view of the oil tank with transparent sides.
The broken lines and stippled shading, which define the oil level in FIGS. 1—3 are for illustrative purposes only and form no part of the claimed design.