In the paper, the issue of sliding sleeves wear in a cycloidal transmission is addressed. The working model of a cycloidal drive was constructed and tested in the special rig, and its sleeves underwent detailed analysis afterwards. The sleeves were produced by sintering technique out of Selfoil bronze with self-lubricating properties. In particular, their surface appearance, weight loss and dimensional changes were assessed, as well as the chemical content of the gearbox oil was analyzed. The differences in the sleeves wear were pointed out, related to their positions in the transmission.