Variants of a mold are catalogued separately, so each one has its own sets and minifigs. Check these too if something you expect is missing here.

• 4180c01 Wheels Train Spoked Small (23mm D.) and Black Brick, Modified 2 x 4 [Black] this part is a sub-part of it
• 4180c02 Brick Special 2 x 4 with Wheels, Freestyle Red this part is a sub-part of it
• 4180c03 Brick Special 2 x 4 with Wheels, Freestyle White this part is a sub-part of it
• 4180c04 Wheels Train Spoked Small (23mm D.) and Black Brick, Modified 2 x 4 [Red] this part is a sub-part of it
• 4180c05 Wheels Train Spoked Large (29mm D.) and Black Brick, Modified 2 x 4 [Red] this part is a sub-part of it