Microtubule-based molecular motor that transport intracellular cargos, such as vesicles, organelles and protein complexes. Uses ATP hydrolysis to generate force to bind and move along the microtubule (By similarity). Plays a role in cilia formation (PubMed:32386558). Involved in photoreceptor integrity and opsin trafficking in rod photoreceptors (PubMed:32386558). Transports vesicles containing N-methyl-D-aspartate (NMDA) receptor subunit GRIN2A into neuronal dendrites (By similarity). {ECO:0000250|UniProtKB:Q61771, ECO:0000269|PubMed:32386558}. This is the function of Ensembl gene identifier ENSG00000101350 (KIF3B, kinesin family member 3B).